Blockhaus d'Éperlecques - Credit: Wikimedia Commons
The Blockhaus d'Éperlecques (, also referred to as "the Watten bunker" or simply "Watten") is a Second World War bunker, now part of a museum, near Saint-Omer in the northern Pas-de-Calais département of France, and only some 14.4 kilometers (8.9 miles) north-northwest from the more developed La Coupole V-2 launch facility, in the same general area. Read more on Wikipedia
Source: en.wikipedia.org