A few blocks from the Aya Sofya, far below the street-level of old-city Istanbul lies the Basilica Cistern, a structure that dates back to the Justinian era in the 6th century. Its purpose was to provide a store of fresh water and it was always kept full as a precaution against long sieges.
The cistern covers a large area of almost 10,000 square meters, most of which are about 2 ft. deep in water. 336 marble columns rising, 26 ft. support Byzantine arches and domes. The 'main attractions' are two carved-stone Medusa head blocks that serve as bases for two of the huge columns which support the arched roof. To allow access, wooden walkways criss-cross the huge cavern and spot lights illuminate the points of interest.
Cool, dark and quiet with the piped-in classical music and the occasional drip of water from the ceiling or splash from the fish that live in the remaining water, the cistern was a stark contrast with the bustling streets above,
and a welcome refuge from the summer heat and a very atmospheric place to visit.