The EDF Bazacle hydroelectric power station is in the centre of Toulouse on the river Garonne. This was recognised as an important water-power site in the Middle Ages, when there were floating corn mills on the river. The great mill of Bazacle was converted into a hydroelectric plant in 1888 by the joint-stock company Société Toulousaine d’Electricité to provide electric lighting for the city. EDF acquired the site in 1946. They opened it to the public in 1989 and it has nearly 120,000 visitors a year. Visitors can see the force of the water in the Garonne from a large terrace that overhangs the river near the weir. Inside, there is a permanent exhibition with animations about the history of the site. Guided tours go to the turbine hall and the tunnels beneath it. There are also collections of older generating equipment and exhibitions of art, energy and biodiversity.