Kosterhavet National Park
National Park Sweden's first marine national park protecting archipelago ecosystems
Kosterhavet National Park spreads along Sweden’s west coast as a marine archipelago: boat trips, kayaking, seal and seabird watching, and coastal fishing draw nature-focused visitors.
Kosterhavet National Park is a marine national park off Sweden’s west coast in Västra Götaland County, protecting the waters around the Koster Islands and adjacent seascapes. It is noted for unusually rich marine life for the region.
The park includes a mosaic of shallow bays, rocky skerries and a deep fjord-like channel that together support diverse species and habitats not common elsewhere in Sweden. Activities include diving, sea-kayaking and boat excursions operated from the islands and nearby mainland harbors.
Kosterhavet was created to conserve marine biodiversity and traditional coastal seascapes under increasing recreational use. Management focuses on habitat protection, fishery regulation and sustainable tourism.
The park lies off the town of Strömstad on Sweden’s west coast, centered on the Koster Islands and the channel between them and the mainland.
- Establishment: Established in 2009 as Sweden's first marine national park, it protects seabed habitats, shallow bays and deep fjord-like channels with exceptional marine biodiversity.
- Activities: Clear summer waters and numerous small islets make the park popular for kayaking, diving and wildlife trips; local operators run guided boat and kayak tours from nearby towns.
What to See #
- Koster Islands: The two Koster Islands form the archipelago's inhabited core and have shoreline trails, small harbors and visitor facilities that serve as gateways into the surrounding marine park.
- Kosterfjorden: Kosterfjorden is the deep, sheltered channel that runs between the islands and the mainland and supports a rich mix of marine habitats from shallow bays to deeper waters.
How to Get to Kosterhavet National Park #
Kosterhavet National Park centers on the Koster Islands off Sweden’s west coast near Strömstad. Drive to Strömstad (accessible via the E6) and take the regular passenger ferries from Strömstad harbor to the Koster Islands; once on Koster the park is explored on foot or by bike and by local boat trips that operate in the park waters.
Tips for Visiting Kosterhavet National Park #
- Plan summer visits when regular ferry and boat services to the Koster Islands run and the sea is calmer, and take the early ferries from Strömstad to avoid the midday crowds on the main islands.
- Use the ferry terminals in Strömstad to reach both North and South Koster, then explore outer skerries by kayaking or joining a guided boat trip to see the park's rich marine life away from the busiest island harbors.
- Many visitors stick to the main village; make time for the smaller islets and tidal shorelines-rock pools and guided snorkeling trips reveal diverse seabed life that's easy to miss from the boat.
Best Time to Visit Kosterhavet National Park #
Visit Kosterhavet in summer (June-August) for the best boating and wildlife-watching conditions; spring and autumn are quieter and good for birding.
Weather & Climate near Kosterhavet National Park #
Continental climate with mild summers (peaking in July) and cold winters (coldest in February). Temperatures range from -2°C to 20°C. Moderate rainfall (733 mm/year).
January
January is cold with highs of 2°C and lows of -1°C. Moderate rainfall (60 mm), mostly overcast skies, and breezy conditions.
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February
February is the coolest month with highs of 2°C and lows of -2°C. Moderate rainfall (42 mm), mostly overcast skies, and breezy conditions.
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March
March is cold with highs of 4°C and lows of 0°C. Moderate rainfall (54 mm) and partly cloudy skies.
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April
April is cold with highs of 8°C and lows of 2°C. Moderate rainfall (44 mm) and partly cloudy skies.
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May
May is cool with highs of 15°C and lows of 8°C. Moderate rainfall (45 mm) and partly cloudy skies.
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June
June is cool with highs of 18°C and lows of 12°C. Moderate rainfall (60 mm) and partly cloudy skies.
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July
July is cool with highs of 20°C and lows of 14°C. Moderate rainfall (54 mm) and partly cloudy skies.
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August
August is cool with highs of 20°C and lows of 14°C. Moderate rainfall (67 mm) and partly cloudy skies.
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September
September is cool with highs of 16°C and lows of 11°C. Moderate rainfall (77 mm) and partly cloudy skies.
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October
October is cold with highs of 11°C and lows of 7°C. The wettest month with 85 mm of rain, mostly overcast skies, and breezy conditions.
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November
November is cold with highs of 7°C and lows of 3°C. Regular rainfall (81 mm), mostly overcast skies, and breezy conditions.
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December
December is cold with highs of 4°C and lows of 0°C. Moderate rainfall (64 mm), mostly overcast skies, and breezy conditions.
