The Grand Bassin is the largest body of open water along the Canal du Midi. It is in Castelnaudary France and covers some 7 hectares (18 acres). Once a scene of intense economic activity, it is now a major pleasure port used by tourist craft. It holds the water reserve for the four locks of Saint-Roche.
Official opening ceremonies for the Canal du Midi were held here on 19 May, 1681.[1]
The basin is exposed to considerable winds, historically even blowing horses and men into the water. A windbreak called Cybele Island (French: Ile de la Cybelle) was built in 1754.[2][3][4][5]