Étang de Lacanau, Freshwater lake in the Landes region, France.

Étang de Lacanau covers approximately 2000 hectares and ranks among the largest lakes in the Landes with a maximum depth of about 7 meters.

In antiquity the Médoc ponds drained into the ocean through an outlet that alluvial deposits, carried by a north-south coastal current, gradually blocked. Hourtin and Lacanau then formed a single lake stretching from Sainte-Hélène-de-l'Étang to Lège, with fishing villages on the eastern shore. Drainage works and the canal des Étangs, dug between 1859 and 1871, lowered the water to its present level, with a maximum depth of 7 m.

The site hosts numerous water activities including sailing, canoeing and carp fishing, drawing enthusiasts of aquatic sports from across the region.

Lake access is available through several equipped boat launch points, particularly at Port Le Moutchic and Longarisse Bay for water activities.

During World War I, Americans established a seaplane base on this strategically positioned lake near the Atlantic coast for military operations.