The city of Tarragona may have been founded by the Phoenicians and was a major city in Roman times that they called Tarraco. There are many archaeological remains from that period but little remains of the second century amphitheatre; after the collapse of the Western Roman Empire, the abandoned structure was quarried to provide stone for building. The Les Ferreres Aqueduct dates from the same period and has survived intact. It was built to supply water to the ancient city and is part of the Archaeological Ensemble of Tarraco which has been listed as a UNESCO World Heritage Site since 2000. The city also houses a cathedral, dating from the twelfth and thirteenth centuries, which combines Romanesque and Gothic architectural features. There are also many historic churches and convents.