As part of the “Battle of Åland” campaign in the Crimean War (1853-1855), Britain and France sought to obstruct Russia’s foreign trade and force Russia to accept peace.
The intention was to render the Russian Navy in the Baltic Sea obsolete by destroying the coastal defence fortresses, vessels and storehouses that Russia used in foreign trade. As most of the merchant ships sailing under the Russian flag at that time were based in Finland, most of the damage ended up being inflected on Finnish property. After the Battle of Åland, the majority of the navigation markers in the Finnish Archipelago had to be rebuilt. Drawings of these new navigation markers remain in various archives.
The Nagu Museum Passage was completed in 2006. This passage goes from Nagu harbour as far as the island of Själö (Seili). The passage is also a part of the Little Archipelago Trail that goes from Nagu to Naantali. The Nagu Museum Passage can be seen from the car ferry on the Little Archipelago Trail, and the entire Museum Passage can be experienced from a private boat or a canoe. The extension of the Museum Passage from Korpoström to Turku was begun in 2007, and will be opened to traffic during the 2008 summer season.