Roman Architecture: Bridges and Aqueducts
The Roman conquest in the peninsula dates from 218 BCD (with the landing of Scipio in Ampurias) to the year 19 AD, with the emperor Augustus, after the Wars with the cántabros (Cantabrian) and astures (Asturians). Their rule ended with the barbarian invasion, at the beginning of the 5 th Century.
Roman art could be divided in several periods: the Republic period (510-30 BCD), the emperor Augustus period (30 BCD-14 AD) and the Classic period (14- on).
Roman architecture - greatly influenced by Greek and Etruscan constructions- is an expression of the practicality and functionality that led Rome to conquer and colonize the wide territory that formed the Empire. Being uniformity and monumentality, some of its most distinctive properties.
Other fundamental features of Roman architecture include the systematic use of arches and different vaults: medium barrel, furnace or edge-on structures; various materials ranging form stone-masonry; mortar-masonry, brick or concrete; monumental proportions as a representation of the greatness of Rome; importance of decorative arts such as mosaics and frescoes. The perfect example of all these characteristics would be the Pantheon in Rome, which is one of the most important buildings in the history of Western architecture.
There were many different manifestations of Roman architecture in Spain that could be divided into religious architecture, urban architecture, memorials, "cultural architecture" -theaters and amphitheaters- and, finally and most important for the purposes of the present unit, construction engineering.
All these engineered wonders were built to serve needs Rome had. They made an extensive network of roads (calzadas, in Spanish) in order to communicate effectively and increase economic and social relations in such a broad territory; it was essential to supply cities with drinking-water reservoirs and aqueducts, as well as to provide them with a sewerage network to clean waste efficiently; sea ports and lighthouses (faros).
Roman Bridges
Many of the Spanish Roman bridges are still in use. The extensive network of Roman roads in the peninsula needed many bridges. Roman engineers perfected them since they were key for access to cities that settled next to the rivers with defensive, and infrastructural - supply and drain- purposes.
Spain possesses an excellent collection of stone arch bridges. It is often difficult to distinguish the roman bridges from their later counterparts. Most of the bridges built later on, in the Middle Ages, were inaccurately considered Roman. Some of the elements to distinguish Roman buildings would include non-lancet arches; elaborated and often padded ashlars; rectangular pillars from the base with triangular or circular enclosed cutwaters; either horizontal or slightly tilted roads, usually more than 5 m. wide.
Puente de Alcántara (6), (Cáceres)
The Puente de Alcántara is one of the greatest Roman bridges. It was built between 105 and 106 AD by Caius Julius Lacer over río Tajo (Tagus river), it is 214 m long and it made up of six arches supported by five pillars and two supports at its ends.
At its center, there is a 13.5 m tall with a 11.5 m by 2.6 m rectangular base triumphal arc that rests on the central pillar of the bridge. There are massive stone retaining walls at each end.
Opposite the end of the bridge, there is a small votive temple, which has a nine-line original inscription on a marble block that includes the name of the builder and a quote that reads, "I have built a bridge which will remain forever". The bottom line of the inscription, which may be apocryphal, gives his full name: C. Julius Lacer. Another inscription in the southern face of the triumphal arch dedicates the bridge to Trajan and refers to the 5 th year of his reign.
The bridge was restored in 1543 and also in 1778, since it was damaged in 1707 during the war of succession. It was completely destroyed in 1809 during the Napoleonic wars and rebuilt between 1858 and 1860.
Puente de Mérida
Over the Guadiana River, the construction of this bridge was one of the basic facts for the settlement and development of Emerita Augusta, founded in 25 BCD and later on, one of the most important culture centers of the Roman world.
Made of concrete (opus caementicium) (7) and covered with big padded stone ashlars, the bridge is 792 m long and has 60 arches. Its construction was divided in sections. The first and second were built at the time of emperor Augustus. In order to strengthen both, they built a common cutwater that collapsed in the 18 th century. For all the restorations from then on, ashlars from the Roman Theater were used.
The first section, still purely Roman, consists of round 10 arches with clear spans between 6.50 and 10 m. In the pillars the Romans built round cutwaters in order to distribute the support.
The second section is much longer, made of 25 diverse aches. This is the part of the bridge that has had most of the structural problems and, therefore, most of the restorations.
After these two spans, Roman engineers made up to five extensions since the river suffered numerous flooding in the west bank. About 22 more arches were built in the times of Trajan.
Puente de Salamanca
Called the Puente Romano, this bridge crosses the River Tormes at the edge of the old town, southwest of the two cathedrals. It is hard to date since there are documents from the times of Augustus, Trajan and Vespasian. Most experts tend to attribute it to Trajan, though.
This bridge was key to the development of the city since it was built in order to access it. The bridge is 356 m long and has twenty-six spans. It is divided into two parts: the Roman one - closest to the town - and the 17 th century extension; both separated by a pier. The Roman bridge has 15 spans (in the north end) of about 9.5 m with pier widths of 2.5 or 2.6 m from 1 to 14, and pier 15 is 6 m wide. The overall length of this part to the centerline of pier 15 is about 201 m. Made of granite; it has square buttresses at each pier, resting on simple triangular cutwaters.
The other newer eleven spans, range between 5.5 to 10 m. long, the pier widths from 3.2 to 3.9 m and, finally, the overall width between the centerline of pier 15 and pier 26 is of 155.2 m long. This part of the bridge has prominent high cutwaters in most of its piers.
Puente de Córdoba
Over the Guadalquivir River, and also referred to as Puente Romano, was built at the time of Augustus as well.
Out of the 17 spans the bridge had when built, there are only 16 left, of which 14 th and 15 th are left form the original. The rest were restored more due to aesthetical reasons than structural, since it had a really strong abutment support. Its spans range from 9.5 to 12 m width.
There are many more Roman Bridges in the Peninsula to be considered, such as the Puente de Alcantarilla (Alcantarilla´s Bridge, Seville), Puente de los Peroches (Peroches´ Bridge, Córdoba), Matapozuelos (Valladolid), Hoz de Lumbier (Navarra), Aluenda (Zaragoza) or Trespuentes (¡lava).
Aqueducts
It is impossible to speak of bridges without referring to aqueducts since they are very similar. The only differences would be that an aqueduct usually is narrow and most of the times, higher and longer than a bridge. An aqueduct is a channel to carry water, and it may be on the ground, below the ground or, above it (in this case, it would become a bridge).
Acueducto de Tarragona
Also called Puente de las Ferreras or Puente del Diablo. Of an Augustan structure, it was built in the 1 st century. This remarkably complete aqueduct was placed about 4 km north west of Tarragona (capital of the Roman province Hispania Citerior Tarraconensis).
Still in an excellent condition, this aqueduct was used until the end of the 18 th century. It was built in two tiers, with eleven arches in the lower one and twenty-five in the upper. The aqueduct is 217 m long and it reaches 27 m height. As for the clear spans, they range from 5.9 to 6.4 m.
Acueducto de Segovia
This aqueduct is probably the finer not only because it is the best preserved of all -still in use-, but also because of its design and size. Made of unmortared granite ashlars. The date of construction is not clear since it lacks inscriptions, even though it looks like there was one in the past. Scholars agree on the second half of the 1 st century AD and early years of the 2 nd, either under Vespasian or Nerva.
It carries water from the río Frío (Cold River) over the Plaza del Azoguejo (Azoguejo square), in the center of the city, to the walls of the ancient Segovia for about 18 km. The bridge part of the aqueduct has a total of 199 semicircular arches (about 728 m). The maximum height is 28.5 m above the ground. The alignment is not straight, so it could be divided in four different parts, being the best known the approach crossing the Plaza de Azoguejo, with 43 double arches and 2 single ones. The upper span is 4.8 m clear and the lower 4.2 m clear.
Other noteworthy aqueducts in the peninsula would be Acueducto de los Milagros (Mérida), San Lázaro (Mérida) and Acueducto de Termancia (Montejo de Tiermes, Soria).
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