On Tjärnö, the marine world can be experienced from several perspectives: the island is home to the University of Gothenburg’s marine research station, and a nearby underwater snorkelling trail in Saltö passes information boards. The island also offers coastal scenery, bathing spots and a church history whose written records date back to the Middle Ages.
Marine Research and Underwater Experiences
Tjärnö marina laboratorium is a workplace and centre of knowledge that shapes the island. It is located right next to Kosterhavet National Park, in the most species-rich marine area in Sweden, in northern Bohuslän. School classes and the general public are welcome at the laboratory. During a guided visit, guests can hear a marine biologist explain the sea and marine environmental issues, see parts of the research and teaching facilities as well as the vessels, visit the aquarium and watch a film about the national park.
Tjärnö Aquarium is home to more than 200 different animal and algae species from the underwater world of Kosterhavet, as well as a Swedish coral reef. A touch pool offers the chance to get to know, among other things, dead man's fingers, cushion stars and sea cucumbers at close range. The aquarium is open to the public in summer; two marine biologists answer questions and give live presentations, for example about oysters, lobsters, crabs or jellyfish. Access may vary from year to year, so it is a good idea to check the latest information before your visit.
The 2026 seasonal programme listed two further marine experiences. On the Marine Biodiversity trip aboard the research vessel Nereus, algae and animals are collected from the seabed and then examined at the station under a stereo microscope. On the “Filmning i Kosterhavets djup” tour, a remotely operated underwater vehicle camera films life 100 metres beneath the boat; the footage is shown live on board and explained by a guide. Dates and availability for seasonal activities may change—check before your trip.
Coastal Scenery, Swimming and Activities
The nearby Saltö Nature Reserve is one of the gateways to Kosterhavet National Park. Its landscape includes rolling woodland, meadows and pastures, with granite as the predominant bedrock. Easy-to-walk trails lead through pine forest, and there are opportunities for swimming, fishing and hiking. The underwater snorkelling trail, about 200 metres long, runs at a depth of 1 to 1.5 metres and has eight information boards underwater.
On Tjärnö itself, the bathing area at Bofors Camping offers practical details: the shoreline is narrow, and the seabed consists of sand and small stones. The bathing area has a car park, toilets and bathing jetties; there is a kiosk in summer. Tjärnö also offers views of Kosterhavet. The sandy beach at Svallhagen is another destination on the island.
Island Chain and History
Tjärnö is part of an island chain south of Strömstad that includes Öddö, Tjärnö and the outermost island, Saltö. The islands are connected by bridges. A characteristic feature of Tjärnö’s coastal landscape is the small, narrow cultivated plots in crevices in the rock—a different view of the island from its marine research and waterside trails.
Written records of a stone church in Tjärnö date back to the Middle Ages; the earliest are from 1391. The present-day stone-built Tjärnö kyrka, however, was constructed in 1855 to plans by the architect Carl Gustaf Blom Carlsson. The two dates tell different chapters in the church’s history. Concerts are held there in summer; the programme may vary by season.
Those looking for more than the sea and history will also find courses and retreats at Gullnäsgården on Tjärnö. The programme includes active relaxation, mindful breathing, self-care, yoga, mindfulness, meditation, health-related topics and Qi Gong. Individual offerings may change, so it is worth checking before making plans.
Plan Your Journey
Bus route 891 connects Strömstad with Tjärnö Aquarium. Route numbers and timetables may change; check the connection before travelling. When choosing where to stay, you can consider which of the themes that matter to you—marine experiences, coastal trails or island history—you want to shape your stay.
Discover more destinations: Lökholmen, Skee, Öfverby, Hogdal, Kebal, Hällestrand, Flåghult, Stensvik.
For the main travel overview: Strömstad.
