Carlsten is a stone fortress built on the orders of King Carl X of Sweden following the Treaty of Roskilde, 1658 to protect the newly acquired province of Bohuslän from hostile attacks. The site of Marstrand was chosen because of its location and its access to an ice free port. Initially a square stone tower was constructed, but by 1680 it was reconstructed and replaced by a round shaped tower. Successive additions to the fortress were carried out, by the inmates sentenced to hard labour, until 1860 when it was reported finished. The fortress was decommissioned as a permanent defense installation in 1882, but remained in military use until the early 1990s.

The fortress was attacked and sieged twice falling into enemy hands. In 1677 it was conquered by Ulrik Frederick Gyldenløve, the Danish military commander in Norway and in 1719 by the Norwegian Vice-Admiral Tordenskjold. At both occasions the fortress was returned to Swedish control through negotiations and treaties.



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Founded: 1658
Category: Castles and fortifications in Sweden
Historical period: Swedish Empire (Sweden)

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User Reviews

alex chaudet (3 months ago)
Very nice island, quiet if you’re not there in the middle of the summer but still beautiful and peaceful place. You have to take a 30 seconds boat to go there (around 34krona/ person round trip) I recommend this place to everyone!
Tomce Angelov (5 months ago)
Beautifull in summer. Lot of things to see and visit. Simply great.
Pasan Hettiarachchi (5 months ago)
Nice well preserved fortress. Even without a guided tour (Swedish guided tour is included in the entrance fee), a lot of exploration can be done. It takes at least a few hours to properly explore it.
Mikael Lundqvist (6 months ago)
Beautifull castle, open for exploration. Some areas really give the feeling how rough life in this kind of prison was
Anders Svensson (9 months ago)
”Carlstens fästning” is a castle located at the top of the tiny island of Marstrand. From the castle you will be able to view around the whole island. Summertime it is possible to visit the castle inside.
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