Creepy Castles: 13 Abandoned Places You Need to Visit
This majestic sea fort, which sits on the bay overlooking the English Channel, was originally built in the 17th century to defend the port of Ambleteuse. It’s located in the Pas-de-Calais in northern France.
Technically, it’s called the Fort of Ambleteuse, but because of a British clerical error in the 1840s, it’s most commonly called Fort Mahon. It was saved from complete ruin in the 1960s by a dedicated group of volunteers who bought and restored the fort, reopening it to the public in the 1970s.