Castellana Caves were first discovered in 1938, and are more than 3 km long and among the deepest in the whole of Italy. The town lies close to the azure sea at Monopoli and the distinctive trulli in the Itria Valley. The town's 18,000 residents are accustomed to tourists here that come to admire their well-maintained and cosy streets and square.
The characteristic caves are among the most beautiful in Italy, and in any case the largest. You need to go underground to start the visit in the huge cave (Milan Cathedral could fit in the cave!). The caves is approximately 3 km long with amazing rock formations with mythological names. During the visit it is possible to admire the water-formed sculptures that resemble terrestrial animals and flowers, stalactites and stalagmites of all possible colours and underground ponds. The longest route is approximately 3 km and it takes about 3 hours to complete (remember to have hiking shoes on, so you do not slip in the wet passages) and leads to the white cave, defined by many as the world's most beautiful. The guided tour costs about 15 Euros. It is not possible to make the trip without a guide.