Bothnian Sea National Park
By the shores of the Bothnian Sea you can enjoy bracing sea winds and fine views out over the wild waves. History comes alive on the park's remote lighthouse islands. Divers can here explore Finland's most pristine marine waters. The National Park is mainly formed by a narrow, long string of barren islets and islands in the outermost archipelago, reaching from Merikarvia to Kustavi. The coastal archipelago is fragmented and rocky. The islands are mostly fairly small in size and the waters surrounding the archipelago are shallow.
The Bothnian Sea is one of the best preserved sea areas on the Finnish coast. Its nutrient content and eutrophication level are clearly lower than those of the Gulf of Finland, Finnish Archipelago and the Baltic Sea main basin.
Though Katanpää has no military importance today, it remains significant for its cultural history, and its harbour is well used by visiting boaters. It is the southernmost of the visitor attractions in the Bothnian Sea National Park. For individual travelers, the island can be reached by boat in the summer from the cities of Uusikaupunki and Kustavi. Isokari Island is an oasis in the middle of the sea. In addition to shorelines of rock and cobbles, the island has lush herb-rich forests, dry meadows and mire meadows. The island's natural surroundings are very diverse both in flora and fauna. Tourists are brought to the islands and, in the summer, there are guided tours of the lighthouse. You can get to the Isokari lighthouse island either by your own boat or, in the summer, by water bus (uusikaupunki.fi) from Uusikaupunki. The island of Kylmäpihlaja and its lighthouse (61°08,6'N, 21°18.3'E) lie about 10 kilometres from the mainland by the open waters of the Bothnian Sea. The lighthouse was completed in 1953, making it the last manned lighthouse built in Finland. Kylmäpihlaja is today a popular destination for visitors, including many birdwatchers. The island's facilities include a restaurant, a café, comfortable accommodation, and sauna facilities. In summer a regular waterbus service runs from Rauma, and visiting boaters can use the facilities in the island's guest harbour. On the formerly fortified island of Kuuskajaskari (61°08.2'N, 21°22.2'E) military relics including four disused coastal defence guns, two watchtowers, and many trenches and other defences are still visible. Today the peaceful island is mainly visited by tourists. It offers accommodation, a café, a restaurant, two saunas and meeting facilities. Along the Kuuskajaskari Trail visitors can learn about the island's history and geology. A waterbus service runs during the summer. The Säppi Lighthouse Island is valuable in terms of its natural heritage: the 150 hectare island holds, on its lush diabase bedrock, a forest that is the object of the national programme for the protection of herb-rich woodlands and important traditional landscapes, among other things. The island is a very important resting place for migratory birds. On the island you can even spot the shy mouflon, wild sheep. Other excursion harbours in the park include Munakari, Iso-Enskeri ja Seliskeri in Pori.