The webcam offers a live broadcast of the Valens Aqueduct, a Roman aqueduct built in the late 4th century AD to supply water to Constantinople, the capital of the Eastern Roman Empire. Construction of this aqueduct began under Emperor Constantius II (reigned 337–361) and was completed during the reign of Emperor Valens (reigned 364–378). This aqueduct was used for many centuries, undergoing expansions and maintenance by both Byzantines and Ottomans.
Originally, the Valens Aqueduct carried water from sources in Danimandre and Pınarbaşı; the channels from each source converged at Dağyenice. The initial phase of this 4th-century system spanned 268 kilometers (167 miles). In a second phase dating to the 5th century, an additional 451 kilometers (280 miles) of pipelines were added to bring water from Visega, located 120 kilometers (75 miles) away from Constantinople.
On the live webcam feed, you can see the last and most remarkable aqueduct in the system, which still stands in the Fatih district of Istanbul, Turkey. Known as “Bozdoğan Kemeri” in Turkish, meaning “Aqueduct of the Grey Falcon”, it’s a significant landmark of the city, with its arches crossing Atatürk Boulevard. Bozdoğan Kemeri spans the valley between hills, where today stand Istanbul University and the Fatih Mosque, formerly the Church of the Holy Apostles. The preserved section’s length is 921 meters, slightly shorter than the original by about 50 meters.