Impressive both for its progressive technological sophistication and great length (1,036 m), how the Efplaineo aqueduct was constructed so perfectly remains a mystery. The tunnel was excavated by two separate teams advancing in a straight line from both ends, digging through solid limestone using only hammers, chisels and picks. The tunnel is located 700 meters from the City of Pythagorio, at the Monastery of Spiliani.
