A military structure located near Saint-Nazaire, France, in the Loire-Atlantique department. The region has a significant military history, particularly as a major Atlantic port targeted by Allied operations during World War II. The specific purpose, construction date, and current state of this site are not confirmed by available historical records or web sources.
The designation 'FA Brunnen' does not correspond to any known, documented military installation in authoritative references on French fortifications or Cold War infrastructure.