A military bunker or battery located near the coordinates provided in the Finistère department of Brittany, France. The name 'Bttr Telgruc' suggests a possible coastal artillery battery ('Batterie') associated with the locality of Telgruc-sur-Mer or a similar toponym. The region of Brittany has a significant military history, including fortifications from various periods due to its strategic Atlantic coastline.
Without specific historical records or confirmed details from the provided search results, the exact function, construction period, and historical context of this particular site cannot be verified. The structure's current state and purpose remain undocumented in the available sources.