Larmor-Baden (French pronunciation: [laʁmɔʁ badɛn]; Breton: An Arvor-Baden) is a commune in the Morbihan department of Brittany in northwestern France. The inhabitants of Larmor-Baden are called in French Larmoriens.

Île de Berder (French for "The Island of Berder") is a small island off Larmor-Baden. In reality Berder is not a true island as it is attached to the mainland by submerged land that shows at low tide. The name Berder comes from the Breton word Breudeur, meaning brothers.

The island lies in the Gulf of Morbihan, and has a position relative to other islands:

• south of Port-Blanc
• north of île de la Jument
• west of île aux Moines
• east of île Longue and the mainland (Larmor-Baden).

• Gavrinis
• Communes of the Morbihan department

• Base Mérimée: Search for heritage in the commune, Ministère français de la Culture. (in French)
• Mayors of Morbihan Association (in French)