The Étang de Thau (Thau pond) is the largest lagoon pond in Languedoc, with its 11.8 miles (19 km) in length and 3.1 miles (5 km) in width. It constitutes a major regional site at the tourist and local levels, with the many craft activities that have developed there. Among them, mussel and oyster farming are facilitated by the local biodiversity and the abundance of phytoplankton in the pond, one of the favorite foods of the mollusks. The Étang de Thau is a true small inland sea home to remarkable biological diversity. It is administratively shared between eight bordering municipalities in the Hérault department.