OB

OB is a military bunker located in the Brittany region of France, near the city of Lorient. This area was heavily fortified during World War II as part of the Atlantic Wall defenses constructed by Nazi Germany. The bunker's exact function and historical role remain unclear from available sources, though it likely served as part of the coastal defense network protecting the strategic port of Lorient, which was a major German submarine base during the war. The Brittany coastline features numerous similar fortifications that were built to defend against Allied invasion attempts.