The Canal du Midi flows over 150 miles (240 km) from Toulouse to the Thau pond and the city of Sète. It includes no less than 64 locks since the construction of the Pont-Canal on the Orb, a bridge that prevents from having to cross the river. Two more locks have therefore been added, one at the entrance and the other at the exit (respectively named Orb and Béziers). The canal displays the ingenuity of its architect, Riquet, when waters are transferred from one pool to another, making the boats rise and go down.