From the Wikipedia page 
Landes (French pronunciation: [lɑ̃d]; Gascon: Lanas Occitan pronunciation: ['lanəs]) is a department in southwestern France.
Landes is one of the original 83 departments that were created during the French Revolution on 4 March 1790. It was created from parts of the provinces of Guyenne and Gascony.
Landes is part of the current region of Nouvelle-Aquitaine and is surrounded by the departments of Gironde, Lot-et-Garonne, Gers, and Pyrénées-Atlantiques, as well as the Atlantic Ocean on the west. With an area stretching over more than 9000 km², Landes is, after Gironde, the second largest department of the metropolitan French territory.