The Greeks dug out galleries 30m-40m below ground in the 4C BC to build the boundary walls of the city. The Greco-Roman Aqueduct (5m high) carried water into the city until 1885. The route then leads to several cisterns built by the Greeks, including one that was transformed into a wine cellar and used by the San Gregorio Armeno Cloister until 1952. The visit ends with the 6 000-capacity Roman theatre (1C-2C), which was discovered in 2002.