The Segovia Aqueduct has existed since Roman times, constructed from approximately 20,400 blocks of granite, most weighing around 1 ton, without the use of mortar.
The Segovia Aqueduct is a classic example of Roman water transport architecture – with a simple yet magnificent design that is remarkably durable. The structure was built to transport water from the Frío River, located 17 km away, to the city, fulfilling this function for over 2,000 years. Impressively, the aqueduct system was constructed without a single gram of mortar.
The Segovia Aqueduct in Spain. (Photo: SeanPavonePhoto/Fotolia).
Segovia is located about 100 km northwest of Madrid, Spain. Initially, it was a settlement of Celtic people, later falling into Roman hands around 80 BC. Under Roman rule, Segovia developed into an important town in the region of Hispania (modern-day Iberian Peninsula).
The Segovia Aqueduct, built from interlocking granite blocks without mortar or reinforced framework, was constructed in the late 1st century or early 2nd century. Scientists are unsure about the exact date because the inscriptions on the stones, which could help determine the construction date, have worn away. Archaeological evidence suggests that the structure was likely built in the early 2nd century, during the reign of Roman emperors Trajan or Hadrian.
Utilizing the natural height, water from the mountains is channeled through an underground conduit to a large reservoir named El Caserón. From there, the water continues to flow to a tower known as the Casa de Aguas. Here, the water is naturally filtered, allowing sand to settle before the water continues its journey, traveling an additional 728 meters across the elevated aqueduct to the Plaza de Díaz Sanz.
With its soaring double arches supported by massive stone columns, the Segovia Aqueduct appears quite impressive. The decision to build the aqueduct without mortar may have originated from a lack of limestone in the area for producing cement. However, this lack of cement may have contributed to the structure’s longevity, as it allowed the bridge to be flexible enough to survive minor earthquakes.
The ancient builders used around 20,400 blocks of granite to construct the Segovia Aqueduct. The largest of these blocks weighs 2 tons, while 1-ton blocks were more commonly used. They were hoisted nearly 30 meters high with the help of wooden cranes, evidence of which remains in the holes left in the stones. The rounded edges of the blocks are partly original and partly due to the weathering of the relatively soft granite over time.
The Segovia Aqueduct has not remained intact for 2,000 years. In the 11th century, an invasion by Yahya ibn Ismail Al-Mamun, the ruler of the Taifa of Toledo, destroyed about 36 stone arches. Some of the fallen stones were later used to rebuild the castle of King Alfonso VI. In the 15th century, the damaged sections were carefully reconstructed to maintain the original design. By the early 19th century, all buildings adjacent to the aqueduct were demolished to facilitate repairs and enhance structural integrity.
Although regarded as one of the best-preserved elevated aqueducts from Roman times, the Segovia Aqueduct today is no longer fully operational. Erosion and decay have caused water to leak from the upper aqueduct, while pollutants from vehicles have contributed to the deterioration and cracking of the granite blocks.
