Photo: Bjoertvedt·CC BY-SA 4.0· Wikimedia Commons
Islands / Hvaler / Tisler
Tisler is an uninhabited island group at the outer edge towards Skagerrak, one of Norway's furthest outposts towards the Swedish border. No one has lived here permanently since 1939. Off the group lies Tislerrevet, the world's largest known cold-water coral reef in shallow water, and one of the reasons Ytre Hvaler National Park protects the sea here.
Tisler is a flat, low island group at the outer edge towards Skagerrak, one of the last Norwegian outposts before the crossing to Sweden. Only Heia lies further out on the Norwegian side. There are no houses to see here. What matters is under the keel: just outside the group lies Tislerrevet, the world's largest known inshore cold-water coral reef.
Nature reserve and part of Ytre Hvaler National Park; check Naturbase for access rules. The boundaries and the rules are in Naturbase, and they are worth checking before you land anywhere outside the marked areas.
Private boat or kayak.
No scheduled boat comes here. You will have to find the nearest public quay yourself, and the rest is your own boat or a kayak. Check the wind and wave forecast before you set out; the open stretches in the outer fjord turn unpleasant in a fresh breeze.
The name comes from the Old Norse *þistill*, thistle, after the shape of the islands, round as seed heads. Tisler has housed up to about 30 people, who lived off the fishing in one of the most weather-beaten spots in the fairway. No one has lived here permanently since 1939.
Tisler lies about nine kilometres due west of the mouth of Dynekilen on the Swedish side, among the southernmost of the Hvaler islands. Together with Herføl it marks the Norwegian outer edge before the border with Swedish waters.
More happens below the water than above it. Tislerrevet is a reef of the cold-water coral *Lophelia pertusa*, built up over a very long time in water unusually shallow for reefs of this kind. It became one of the main reasons the whole area was protected: when Ytre Hvaler National Park was established on 26 June 2009, the reef was among the marine values the park was meant to safeguard.
Tisler is uninhabited and used for outdoor recreation, with a swimming spot for visitors. The group is part of Ytre Hvaler National Park, which covers 354 km² across Hvaler and Fredrikstad, of which 340 km² is sea. The park borders Færder National Park to the west and the Swedish Kosterhavet National Park to the south, making one continuous protected sea area across the national border.
Tisler is reached only by private boat or kayak. Parts of the island group and the surrounding waters are nature reserves inside the national park, with rules for traffic and activity. Check Naturbase, the national database of protected areas, for exact boundaries and access rules before going ashore or anchoring, particularly in the nesting season. The protection rules are law rather than judgement: look the dates up, do not guess them. Do not anchor or trawl over the reef itself.
Tislerrevet is the world's largest known inshore cold-water coral reef. Most people assume cold-water corals grow only at several hundred metres depth; this one sits in unusually shallow water inside the skerries, protected within the national park.
Tisler is close to the end of Norway on this side: only the islet of Heia lies further out towards Skagerrak.
The group is among the most weather-exposed places in the inner Skagerrak. That people lived here permanently until 1939 says more about the fishing than about the comfort.
Oslo Sea Experience passes Tisler on its private fjord trips from Tjuvholmen.
The Norwegian version notes which facts were taken from each source: Tisler på norsk.