Fort de Bertheaume

Plougonvelin, France

The Bertheaume fort is a small part of the large coherent system of small forts and batteries designed to protect the entrance to Brest harbour. It is situated on a small island just 100m off the coast of the town of Plougonvelin. It was only accessible at low tide by foot over a rocky bank, attackers had to climb the steep cliffs first to reach the walls of the fort, an impossible job.

The medieval fort that used to be situated on the island was destroyed during an English attack in the 16th century. On his inspections of the Brest region in 1683 the famous architect Sebastien Vauban had already noticed the strategic value of the island and wanted to build a battery there.

The first cannon were placed there during the English attack in 1694 and the fort was finished in 1699. The original fortifications where situated only on the large island. The buildings on the smaller island closest to the mainland date from the 19th century. The fort on the large island consists of batteries for cannon on 4 levels connected with stairs. At some places the bases of the chauguettes can still be seen on the walls and posterns gave access to the foot of the walls.

In the past the island was only accessible by a boat at high tide. This was a small boat connected to a rope running from the mainland to the island. By pulling the rope the boat went to or from the island. The current steel bridge dates from the 20th century. In the late 19th century the fort was abandoned and was replaced by the more modern casemated fort on the mainland. The Nazis built a small blockhouse on the island.

In the 1990s the Fort de Betheaume was restored and opened to the public. Apart from the visit of the fort it also offers a survival track (only available when the weather conditions allow it). The fort is open to the public all year round. A small restaurant and various exhibition rooms are located in the 19th century fort. There you can also visit the underground powder magazine, carved in the rocks 13m below ground level.



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Founded: 1694-1699
Category: Castles and fortifications in France


4.5/5 (based on Google user reviews)

User Reviews

Igor Kelavic (10 months ago)
One of the best one day trips in my life? Pure combination of old military and nature art. Recomend to see 100%.
Aaron Gregory (10 months ago)
It was quite nice and the views are the top of the fort we're really good. The walk up to it had some nice scenery as well.
Chris Ryan (14 months ago)
Interesting old fort location. Does it really need a zioline? Closed as of April 2023, but you can get close for great views by walking along the water. Other entries are closed off for construction.
Neil Goodwin (2 years ago)
We had great fun here. I visited with two teenagers and we all really enjoyed the adventure. Spectacular scenery. We spent about two hours completing the full course. The older teen did the Black Route (hardest) and myself and the 13 year old did the Red Route. Even this route was challenging, but great fun. Going down into the cave was the most exciting bit. The two zip lines were awesome. Very good value for money and all the equipment was in very good condition. We felt very safe all the time. We would love to visit again.
Steven Toms (2 years ago)
Visited out of season but a beautiful place draped in history. And any submarine buff will love the pictures and models plus bits on submarines. For what it cost to visit I'd have paid double for a historical place like this. A bargain for a few euros. And a great few hours of your holiday.
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