Koster Islands & Kosterhavet · Sweden · Wall · Sand slope
Inre Vattenholmen
Sea hares and nudibranchs in plenty in early spring
Inre Vattenholmen is an island near Tjärnö where a natural dive circles the whole shore. A classic west-coast cliff drops to 14 m and gives way to shell gravel on the outer side, and divers come for the ballan wrasse and edible crabs and the sea hares and nudibranchs that are plentiful in early spring.
Also known as Inre vattenholmen.
Where it is and how deep
58.8773° N, 11.1137° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
The route runs around the whole island. A classic west-coast cliff drops to 14 m, with ballan wrasse and edible crabs plentiful along it. On the outer side the cliff ends on a shell-gravel bottom that runs on down to about 30 m, and out there mackerel are sometimes seen. In early spring sea hares and nudibranchs are plentiful.
Marine life and season
- Nudibranchs
- Macro critters
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Good | Good | Good | Fair | Fair | Fair | Good | Good | Good | Good | Good | Good |
Season follows Koster Islands & Kosterhavet: Boats run all year and no month stands out; spring and early summer bring brown, low-salinity surface water.
Know before you go
- The water around the sandbank is very shallow, so the boat needs care with depth when anchoring.
Questions divers ask
How is Inre Vattenholmen reached from the boat?+
Boats either anchor off the beach and divers surface-swim out to the island, or the bow is wedged onto the island itself; the sandbank is shallow, so anchoring needs care.
Sources
- Inre Vattenholmen dykplats | dykarna.nu — dykarna.nu
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