Engineering Rome: Trajan’s Forum



By Aaron Couch / 10.26.2015
University of Washington

In a city full of engineering marvels and tourists attractions such as ‍‍‍‍‍‍the Colosseum, the Pantheon, and St. Peter’s Basilica, it is hard to imagine that for centuries the most visited and important places in Rome were the public forums. A Roman tradition from their inception, the forums grew to become the heart of the city. The last of these forums to be built was also the largest. Built by one of the Roman Empire’s greatest emperors, Trajan’s Forum was one of the largest and most important construction projects in Rome for centuries.

Roman Forums

Figure 1: Layout of Roman forums (Packer, 1997)

Forums were an integral part of the ancient Roman culture. As the city was forming, the inhabitants of the 7 hills chose the valley between the Capitoline, Esquiline, and Palatine hills as the common meeting point for trade. The site was close to much of the population and had level ground to set up shops. In order to use the swampy lowlands they first needed to drain the water. To do so, the early Roman people built the Cloaca Maxima that spanned the entire valley north to south (Packer, 1997). This early forum was where the people brought their cattle, fish, pigs, vegetables, fruits, as well as ceramics, oils, and other goods to trade and sell. Originally this was done in the open square, but eventually shops were established. Later, other buildings for worship and political functions were established. Italian archaeologist Pietro Romanelli wrote that “the forum in every Roman city was not so much the topographical centre as the very hub of its life; in the Forum, and in the buildings surrounding or near it, every political, religious or financial event concerning the existence of the city had it natural seat, developed and matured. Nothing, not any single event ever occurred in the history of Rome without its having its echo in the forum, whence it either started or where it was reflected.” (Romanelli, 1983)

As the Republic of Rome became the Roman Empire, the early Emperors focused on improving the forums infrastructure for their subjects. Julius Caesar began the first of these projects, which was completed by his heir Augustus: the Forum of Augustus also known as the Roman Forum. Emperor Vespasian followed suit and built the Forum of Peace to the south of the Forum of Augustus. The Emperor Domitian connected the two forums with the “Forum Tranitorium” (Packer, 1997).‍‍‍‍‍‍ Domitian also had planned to build another forum outside of a large palace for himself to the north of the Forum of Augustus, but died before its completion. Figure 1 shows the layout of the forums after the completion of Trajan’s Forum. Nerva was appointed Emperor after Domitian and halted work on the forum indicating that the extravagant plans of Domitian were unwarranted and the Empire needed to focus it’s budget elsewhere. Nerva’s short reign from 96-98 led into the reign of Trajan.

The Emperor

Figure 2: Bust of Trajan / (Photo by Aaron Couch)

The Forum was built under the direction of the emperor Trajan. Caesar Nerva Traianus Divi Nervae filius Augustus, born Marco Ulpia Trajan and commonly known as Trajan, is widely considered one of the Roman Empire’s greatest rulers for his military success and successful domestic policies. Many depictions of the Emperor remain today, like the statue shown in Figure 2. Trajan’s father was a decorated military general who commanded a legion of the Roman army. After his military service, Trajan’s father became the governor of Rome in Syria and Asia, a position that led to his appointment to the Senate and his son Trajan becoming a part of the highest social class. Trajan followed in his father’s footsteps by training under a military apprenticeship and commanding a legion of his own (Hammond, 2015). Originally based in Spain, Trajan was called to the borders of modern day Romania to defend the Empire’s borders from Dacian tribes. During his time in Dacia, the emperor Domitian was assassinated and Nerva ascended to the position. Nerva was appointed very late in his life and was only emperor for 2 years. He adopted Trajan as his successor because of his appeal to both the military commanders as well as the higher class Senate (Hammond, 2015). Trajan took over as emperor of Rome in 98.

Reigning from 98 – 117 AD, Trajan’s expanded the empire to its largest extent. It encompassed the Mediterranean Sea, stretching from modern day Northern Africa in the south to parts of Great Britain, the Netherlands, and Ukraine in the North and from Portugal in the west to Iraq in the east. Trajan enacted policies of public welfare that used public funds to provide grain to poor families and established the first public welfare system in the world intended to support poor children. Trajan also undertook massive public improvement projects: building roads, harbors, buildings and aqueducts. His most notable work took place within the empire’s capital: Trajan’s Forum. Trajan’s forum was the largest imperial forum ever constructed in Rome and one of the Roman Empires most impressive engineering feats.

History

Trajan’s forum was built to commemorate Rome’s victory over the organized and dangerous tribes of Dacia in the northeast. Many of the lands that the Roman Empire conquered were settled by poor, untrained populations without an organized military or defenses set up to withstand the onset of a large Roman Army. The people of Dacia were much more organized and dangerous. The Dacian tribes were trained warriors and were friendly with several of their neighbors that Rome also considered enemies. They had been united under a common king, Decebalus, who organized them into armies similar to the Roman style. The Dacian’s regularly raided the Roman Empire for supplies.

When Trajan became emperor, Rome was suffering economically due to many long military campaigns and the previous frivolous spending of the Emperor Domitian. The land of Dacia was rich with natural resources such as gold, iron, and copper. With no defense in place to properly defend its borders and the potential economic gain from the Dacian mines, Trajan prepared for war.

Trajan’s conflict with the Dacian’s lasted two wars. In 101 AD, Trajan marched on Dacia burning towns and villages. Trajan employed the architect Apollodorus of Damascus to design a bridge across the Danube River, Europe’s second longest river (Packer, 1997). The bridge is considered the largest ever built at that time and for centuries thereafter. After mounting in ineffective resistance, the Dacia king Decebalus choose to make peace with the Roman’s rather than risk additional conflict. As part of their treaty agreement, Trajan supplied the king with weapons and resources to rebuild their military as a means of protecting the Roman Empire from the surrounding territories. By 105 AD the Dacians were no longer listening to the Roman authority and revolting. Trajan again marched on Dacia this time advancing to the capital. King Decebalus committed suicide to avoid capture, but Trajan had conquered Dacia (Curry, 2012).

The spoils of the war have been hard to quantity, but one contemporary chronicler boast that Trajan brought back with him half a million pounds of gold and half a million pounds of silver (Curry, 2012). The victory also gave Rome a fertile new providence to settle and tax.

Having successfully conquered Dacia, the emperor commissioned the architect Apollodorus of Damascus to design a forum that celebrated Trajan and his victory. Apollodorus was a very successful engineer and architect; he has been credited as being one of the designers of the Pantheon. He designed the 25 acre area to include many amenities for the Roman public.

Design

 

[LEFT]: Figure 3: Plan View (Galinsky, 2010)
[RIGHT]: Figure 4: Reconstruction of Trajan’s Forum (Packer, 1997)

The complex design was most likely drawn out on papyrus paper. Vitruvius speaks of ichnographia, made with a compass and ruler. This would have been a floor and elevation plan for the build. These scaled drawings probably used colors to signify the different marble designs and frescoes. Intricate details would have been worked out with scale models made from wax or wood. Unfortunately none of these documents or models has ever been discovered (Packer, 1997).

The entrance to the forum was on the southern wall face. Romans passed under a triumphant arch crowned with a bronze statue of Trajan driving a six-horse chariot. Immediately passed the archway, the forum opened up into a large open square. In the middle stood another bronze equestrian statue of the Emperor. Along the east and west sides of the square stood roofed colonnades with apses. To the northwest of the square stood the Basilica Ulpia. On the north side of the basilica stood Trajan’s column flanked on east and west by two libraries. Further northwest, behind the column stood a temple. Outside of the forum, but immediately north, Trajan built his markets. Construction for the forum and basilica began in 106/107 AD and was completed in 112 AD. The next year the markets and column were inaugurated. The temple is thought to have been included in the original design, but it was ‍‍‍‍‍not completed until 11 years after Trajan’s death in 128 AD. Figure 3 shows a plan view of the forum and Figure 4 shows a three-dimensional reconstruction of the forum after its construction.

Apollodorus designed the forum as a triumphant climax to the series of forums. The city of Rome grew out of necessity with little city planning. The streets are not laid out in a grid, buildings are of various sizes, and new structures needed to conform to what already existed around them. This principal of Rome holds true for the forums as well. Apollodorus’ plan would attempt to unify the three forums together and make sense of the uncoordinated assembly of buildings.

Apollodorus was limited by geological constraints. The new forum was to be placed on the land set aside by Domitian for his palace. This was between the Quirinal and Capitoline Hills. There was also several street and buildings that needed to be removed. It is presumed that these buildings were part of a public market and would be moved to the newly planned Trajan market. The land was also on a slope. Part of the Quirinal Hill would need to be leveled before any building could commence.

‍‍‍‍‍As it can be seen in Figure 1, above, the north-south axis ‍‍‍‍‍extended from the Forum of Peace in the south. He used the columns in front of the Temple of Venus in the Forum of Caesar to set the front line of the new forum. Apollodorus then laid out Trajan’s forum as a mirror image of the Forum of Peace, with the Basilica Ulpia acting as the Temple of Peace. The open square in front of the basilica mirrored the gardens in front of the Temple of Peace. Also, the length of the court in front of the Forum of Peace is 400 Roman feet. This is the same length and width of Trajan’s forum square if you include the colonnades. In addition the Basilica is 200 Roman feet wide and 600 Roman feet long, or 0.5 times as wide as the court of Temple of Peace and 1.5 times as long (Packer, 1997). Different from all the other forums, Apollodorus included a basilica as the background for the square instead of the temple. A temple was included in the design, but this was added after Trajan’s death by his successor Hadrian.

Apollodorus was also limited by the materials he had available. Today, we understand material properties better and can manipulate them to fit our structural designs. Apollodorus accepted the materials for what they were and designed around their strengths.

Materials and Labor

Figure 5: Travertine Quarry in the nearby city of Tivoli (photo by Aaron Couch)

Much of the site was built utilizing existing materials found within or nearby Rome. Tuff deposits are naturally prevalent in the area. This type of rock was named peperino and is the product of volcanic deposits that happened long before hills of Rome were settled, approximately 500,000 years ago. Travertine, a porous calcium carbonate, could easily be ‍‍‍‍‍quarried or mined in nearby Tivoli‍‍‍‍‍. This stone was easy to cut into workable shapes for building. Marble could be found in Northern Italy, near Carrara (Gates, 2011).

Roman’s understanding and ability to use concrete was a new step in the field of engineering. Earlier societies had been limited to the use of post and lintel construction: a horizontal member supported at its ends by two vertical members. A famous example of this can be seen in the Greek Parthenon.

Much of the building at this time in history consisted of bricks. These bricks were mass manufactured and each one was stamped with the manufactures seal, as they were responsible for its quality. Standardized sized clay bricks were used for the form of structures and were filled in with concrete. The concrete that the Romans used was considerably weaker than the concrete used today: Roman concrete has a compressive strength of about 6 MPa. The Roman’s burnt limestone and volcanic ash, such as the abundant volcanic ash tuff, to produce quicklime. Vitruvius’s De Architectura (~15 BC) sites the proportions as 3 parts ash to 1 part lime (Gotti, 2008). It was then combined with water to create a paste. Next, larger aggregate such as chunks of debris, rocks, or brick were added to create concrete. These were common, but the Romans used many different types of aggregate. A study by MD Jackson compared the material properties of concrete composed of different aggregates and compiled the results in Figure 6 below:

Figure 6: Jackson (2009)

While it may not have the strength or resistance as modern concrete, Roman concrete has proven to be very durable.

Roman concrete lacks reinforcing steel. This means all of the material’s strength comes from the mechanical bond between the rock and the mortar as a function of roughness and porosity of the surface. The mortar could be compacted into the pores created by the large aggregate which when dried creating a strong interlock. While this limited its constructability, it can help to better preserve the concrete. Corrosion of the steel can accelerate concrete’s decay. Meanwhile, in Roman concrete, the chemical reactions that formed between the limestone, water, and aggregate have resisted chemical decay and damage. Vitruvius also discussed the structural tendencies of travertine, such as its tendency to split if stood on end. Today this phenomenon can be explained because of the stone’s much higher compressive strength compared to its tensile strength. Apollodorus designed the forum to take advantage of these material properties.

During Trajan’s rule, he enacted policies that strengthened a slave owners control over their slaves. During his reign, if a master was assassinated, all of his slaves were condemned to death. It is assumed that many slaves were employed during the construction of Trajan’s forum. There is no historical record of the cost of the forum, but it has been assumed that slave labor was used to save costs. Trajan and the subsequent Emperors used the forum to burn tax records. But given the scale of the project, the high quality materials used other than brick and concrete, and the intricacies of the design there was considerable expense for the public construction project.

Site Preparation

To prepare the site for the new forum, first large portions of the Quirinal and Capitoline hill needed to be removed and the ground leveled. The Quirinal hill, at the north of the site, is made of tuff. A large spur needed to be removed; the top of Trajan’s column is supposedly the height that the spur once reached. There were shops or apartments located on the hillside that needed to be demolished as well. To cut away the hillside, manual labor was used. Roman technology at the time consisted of iron tools as well as some stone hammers and wedges. Workers would use an iron pry bar and strike it with a stone hammer to remove hard stones and rocks. Wooden wedges could be used to split rocks when struck with a hammer as well. They had curved iron pick axes to break away softer rocks. Wooden baskets, buckets, and sleds as well as cloth sacks would have been filled with dirt and rock to transport it from the site. Romans may have had wooden wheelbarrows, but there isn’t any conclusive evidence to prove they did.

Figure 7: Roman Chorobates. (Survey)

In Vitruvius’s De Architectura, he describes the Roman surveying techniques. Using a ‍‍‍‍chorobates‍‍‍‍, a 20-foot long rod with identical legs attached to either end and plumb bobs hung over the rods side. Attached to the legs is a diagonal rod with vertical lines carved into them. When the chorobates was placed on the ground and the plumb bobs were aligned with the vertical marks, then the ground was level. The instrument also had a water level built into the top of the horizontal 20-foot rod. Figure 7 shows a drawing of how a Roman Chorobates. To record vertical changes, two chorobates were set up and leveled, than a rod could be placed on the lower ground and the vertical distance to the upper chorobate was measured via tick marks of known distance along the rod (Lancaster, 2000).

Figure 8: Romans Groma (Cornelius)

The Roman’s also used an instrument called the ‍‍‍‍groma‍‍‍‍. This helped them to set out straight lines and right angles. As shown in Figure 8, the groma consisted of a metal rod with an equal-armed cross attached flat to the top of the rod. From each end of the cross was a plumb blob. A surveyor would set up the groma plumb with the ground and turn the cross in the direction that the line was to be set out. His assistant would walk out a distance and place a marking pole in line with the direction the groma was pointing. This would continue until the assistant was out of earshot or the surveyors’ sight line. Then the surveyor would move the groma to the farthest marker pole, reset his instrument and continue the procedure. For right angles the surveyor would establish the line as before, but send out the assistant in the direction that the side of the cross was pointed (Lancaster, 2000).

These techniques could be used to set cross axis and mark the centers of the basilica, market, column, libraries, and apses as well as the structures corners. The entire perimeter was lined with blocks of tufa and travertine.

Archway

Figure 9: Opus Quadratum building technique (Acocella)

When the forum was excavated the central archway was not found, so historians have relied on architectural fragments to interpolate how it looked. The archway was depicted on the gold coins minted by Trajan himself. A marble wall encloses the forum with the entrance to the forum lying on the southeast side. On either side of the central arch were two smaller lateral arches. The north and south side of the central archway were most likely mirrored. Archaeologists have estimated that the arch had the same length as the central porch of the basilica with a 31 m in width, about 28.5 m high (Packer, 1997). The use of arches was one of the ways that Apollodorus was able to capitalize on Roman concrete’s high compressive and low tensile strength. Arches are also able to span greater distance than straight beams while supporting a heavier load. They more efficiently distribute the load across their entire member length and to the ground. This loading creates a large thrusting force at the ends of the arch that needs to be braced. The central archway was a part of a larger wall that surrounded the entire square.

The wall was constructed of pre-cut travertine blocks. The Romans used a construction technique known as opus quadratum for the wall. This is a way of assembling the block walls without the use of mortar. Roman’s laid square blocks along parallel courses. The next lay of blocks would be centered over the joints of the blocks below. This wall was only one block wide (Lancaster, 2000). An example of an opus quadratum wall is shown in Figure 9.

The gateway had four columns that created four entries ways below the archway. Atop the archway were statues referencing the Dacian wars. One such statue is believed to have been the statue of the Dacian king Decebalus, which is currently on display in the Vatican museum.

Square

Figure 10: Trajan’s Forum, Sept 2015. (Photo by Aaron Couch)

The courtyard measures 600 feet by 360 feet. ‍‍‍‍The ground that can be seen today, see Figure 10, is the relic of medieval houses and churches built in the forum around the year 1000‍‍‍‍. During the Roman Empire this forum was covered with white marble stones. During construction, after the ground had been dewatered and leveled, a layer of concrete was poured. On top of this layer the foundation/pavement blocks of marble would have been installed. To install these, two timber logs were set up vertically into the ground in the form of an inverted “V”. Using these logs as a frame, two pulleys would be installed along their apexes. Ropes pulled by oxen would hoist the marble into position to be placed.

Aligned with the lateral archways on either side of the center archway leading into the forum stood two rows of trees. Lining the forum square stood the porticoes and apses.

Porticoes and Apses

Roughly half a meter higher in elevation than the square, stood rows of marble columns supporting a vaulted ceiling. These porticoes opened up into spacious semicircular apses. The foundation of these structures consisted of poured concrete. Since the square is at a lower elevation, it is assumed that the colonnades were built after the square’s foundation was in place. A layer of lead would have been placed along the square’s marble stones to protect the marble from the concrete. This lead, along with the outlying travertine blocks along the straight portions and peperino blocks along the apses, acted as a formwork for the concrete pour.

From the square, three steps led into the portico’s rectangular open space. The outer walls of the structure were composed of precut peperino blocks. Stone masons cut holes in the top and bottom of the blocks for iron pins to be set. To connect the blocks, the socket in the lower block was filled with molten lead and the pin along the bottom of the top block was placed into. When all the pieces were in place and cooled, the stonemason would finish and polish the surface. All along the outside walls of both colonnades and apse were niches for statues.

Figure 11: Eastern Portico on Sept 2015 (Photo by Aaron Couch)

The colonnades ‍‍‍consisted of 22 columns set in a straight line along of sides of the square‍‍‍. Figure 11 shows the area in September of 2015 of where the eastern colonnade once stood. In the picture, the steps can be seen that would have led from the main square to the inside of the portico. Only the bases of the original colonnade columns remains. The brick column in the foreground was not part of the original design. The columns were solid pieces of Corinthian marble. Quarried in Italy or Greece, they would be shipped up the Tiber River to Rome and received their final finish onsite. The bases would be built out and then oxen pulled cranes would set the column. The ornate edges and designs would be constructed onsite by skilled workers using chisels and picks.

Nothing remains of the ceiling or rooftops. But there is no evidence of a drainage system and the fine marble pavement, which would indicate there once was a roof. These are thought to be wooden trusses along the colonnades. For the apses, Apollodorus designed walls thinner than those used in the Pantheon. They would not have supported a dome with a central oculus. It is assumed that a half-cone shaped roof supported by trusses was employed. Windows were set in the upper level to light the area.

Walking the length of the colonnades would have led to an entrance to the Basilica Ulpia. A single column along the colonnade is recessed into the entrance archway wall connecting the column to the basilica. Some archaeologists conclude that this signifies that the colonnades were originally conceived as wings of the Basilica and not free standing structures.

Basilica

Figure 12: (Unknown Author)

The Basilica Ulpia was the largest structure included in Trajan’s forum and was the largest basilica in ‍‍‍Rome‍‍‍ at the time. Its name is derived from Emperor Trajan’s family name. Twice as high as the colonnade and 1.5 times the width of the square including the porticoes, the Basilica split the forum into two parts. It had five entrances facing the forum square: one in the center opposite the central forum entrance archway, two equal distance between the ventral entrance and the beginning of the porticoes, and one at either end of the porticoes. The building consisted of one central room, four aisles formed by supporting columns, and an apse at either end. Large portions of the building were open to the outdoors, making it more of a pavilion.

The building was supported by a concrete foundation. The nave was a rectangular space of 300 Roman feet by 85 Roman feet (89mx25m). The nave was two stories with horizontal blocks set across the columns with another set of columns on top supporting an upper roof. The roof of the main nave was predicted to have been built out of wooden trusses. Vitruvius discusses truss roof systems in his manuscripts, but nothing of the size of the basilica. Archeologists consider the design to be very similar to those used in the original St. Peter’s basilica and the 9th century St. Paul Outside-the-Wall. A king and queen truss would have been centered over each pair or columns. The vertical king and angled queen members act in tension, supporting the lentil beam from above. These trusses would have been made of cedar of fir. Stucco would have been installed on the underside of the trusses to allow for decoration.

Figure 13: “Cheap” Column (Photo by Aaron Couch)

Surrounding the nave was a double row of columns. These 96 columns formed aisles 5 meters wide. Unlike the solid marble columns used in the porticoes, these columns were “cheap columns” constructed of brick and then faced rather than monolithically quarried. The columns supported a barrel-vaulted ceiling made of concrete supported this structure. Fragments of the concrete assumed to have been a part of these ceilings have been examined and contain an imported volcanic rock scoria (Packer, 1997). It is theorized that this was done to limit the weight of the ceiling material. Without knowing the exact dimensions of the ceiling it is difficult to say if this material change was necessary, but it can be assumed that the Romans were aware of the materials weight and its effect on bearing a load.

Trajan’s Column

 

[LEFT]: Figure 14: Trajan’s Column (Photo by Aaron Couch)
[RIGHT]: Figure 15: Column Inscription (Photo by Aaron Couch)

Towering over the forum stands the 126 foot (38.4m) tall Trajan’s Column. Made of sculpted marble depicting the victory of the Roman army over Dacia, the column was topped with a bronze statue of Trajan himself. Today the statue of Trajan is gone and instead a statue of St Peter has stood in its place since 1587. The artwork looks to be designed as one giant continuous scroll depicting Trajan’s Dacian Wars. If the tower could be “unrolled” it would be almost 200 meters long. Trajan is depicted as the hero of the narrative and is shown 155 times.

Inaugurated in 113 AD, ‍‍the column ‍‍sits on a square travertine foundation and a marble pedestal. Twenty-one sculpted circular blocks of marble make up the tower of the column. These blocks were sculpted by stonemasons on the ground and then set in place by cranes. The columns foundation rests on a bed of sandstone, which gives it a solid foundation that protects it from earthquakes.

On the interior a spiral staircase of 185 steps is carved into the marble and the top is accessible. The corridor is not round as the outside of the column’s cylindrical shape may lead you to believe, but instead consists of 90 degree angles. About 12 meters above the foundation is a room with a small door. On his death in 117, Trajan was buried in the inside the city, which was only bestowed to few Romans, in the base of the column.

Figure 16 is a short video created by National Geographic discussing the history and construction of Trajan’s Column.

Libraries

On either side of Trajan’s Column, stood a library. These were quite large for their time their dimensions measuring 20 meters wide by 27 meters long by 15 meters high. The buildings were divided into Greek and Latin collections. The foundation for the libraries would have been poured when the basilica’s was poured. Bricked faced walls were decorated with frescos and marble as decoration. A wooden truss roof similar to the one used on the basilica is thought to have been employed.

Market

Figure 17: Trajan’s Market (Photo by Aaron Couch)

Physically separate from the forum was Trajan’s Market. Unlike the open square and spacious forum, Trajan’s market was a dense multi-storied structure set up for public trading. It was essentially the first shopping mall with over 150 public stalls and offices.

The market was built on a hill rather than cleared level ground. Part of the hill was cleared away and the building was actually built into the hillside. This allowed the structure to act as a retaining wall for the earthwork behind it and help to stabilize the hillside. Most of the structure was created with a brick opus quadratum wall filled in with concrete. Many of the shops are small. Walking through the facility they vary in size, but all have brick walls with a brick half-domed room that creates a semicircle with the front wall. Customers would approach the shopkeeper at the door and be served from there. They wouldn’t actually enter into the room. Large hallways connect the different shops and steep stairways lead between floors. The third and uppermost floor was not part of the original structure but was added years later to expand the facility and help to stabilize the hillside behind it.

Figure 18 Materials used in building Trajan’s Market (Photo by Aaron Couch)

The market’s central hallway is considered an important creation in the architectural revolution. Much of this is due to the Roman’s ability to work with concrete. A rectangular room measuring 8.5 m wide by 36m long, the room was built with travertine block walls filled with concrete and faced with bricks (Brune). The ceiling is groin vault made entirely of concrete. It was one long barrel vault intercepted by 6 perpendicular barrel vaults. These intersecting barrel vaults act as a lateral arch in 2D that diverted the load of the ceilings onto thicker portions of the building below. The brick arches sat atop brick pillars and unloaded their thrusting forces on the walls of the second floor rooms. These arches not only helped reduce the need for load bearing walls but also allowed for light to enter the space. This was a groundbreaking point in construction as nothing this large or complicated had been achieved before.

Figure 19: Vaulted Ceiling of the Great Hall (Photo by Aaron Couch)

While the design and final product is groundbreaking, the construction process was also impressive. Wooden panels would have been used as formwork to pour the concrete. The order of construction would have to be carefully planned so that each pour had time to solidify and the structure remained in equilibrium. These wooden forms also needed to be created in such as way that they could be loosened and removed when necessary.

Collapse

Figure 20: Author at Trajan’s Market

While the markets are still standing much of the forum has deteriorated. The forum was subject to hundreds of years of weathering, flooding, and earthquakes. In 330, the Emperor Constantine split the Empire into two parts: Western and Eastern Rome. The city of Rome was in the Western Empire. The empire developed many economic, religious, and governmental problems and Rome began to diminish. The empire fell in 476. The city fell under Papal control, with various states influencing the city’s uses as the historic empires of Europe rose and fell. In the 1870 the Italian state’s were uniformed into the Kingdom of Italy and Rome was made the capital.

The forum and markets went through many different renovations and remodels as the structures were conformed to fit the city’s current need. Throughout the ages, the marble and the statues where looted because of their value. With the fall of the Western Roman Empire, the population of the city diminished dramatically. For hundreds of years many of the city’s landmarks and buildings were too much to maintain for the dwindling population. Earthquakes weakened and collapsed structures. Floods brought in layers of mud and soil that buried the monuments. Invasions by hostile armies destroyed buildings and changed the landscape of the city. In the 1500’s, as the population of the city began to rebuild after the dark ages, buildings were erected in the forum’s open space for the community to use. The city was rebuilt as the new capital of the Kingdom of Italy, only to be bombed during World War I. It witnessed a substantial growth after the war becoming more modern and beginning to see a rise in population that has continued to modern times.

Trajan’s forum was first excavated in 1810. There have been various excavations since, the largest initiated by the federal government in the 1920’s. Slowly more and more of the original forum and surrounding area has been unearthed and historians have pieced together a clear picture of life in ancient Rome. Today the market and the forum are open again to the people of Rome as a museum. The forum is also home to another one of Rome’s growing populations: feral cats.

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