Castelnaudary is a market town, and the capital of the territory of Lauragais. The town is located 50 kilometres (31 miles) southeast of Toulouse, about midway along the route from that city to the Mediterranean. This route has been used since at least Roman times, and today carries road, motorway (A61), rail and canal links. Castelnaudary is the main port of the Canal du Midi to which it owed a period of prosperity in the 17th century when agricultural and manufactured produce became easier to export. The Grand Bassin in the town is at 7 ha the largest open area of water in the canal, and is today its major pleasure port.