Dive or snorkel with the bird life – puffins and guillemots swoop deep as they search for food – with local company Arctic Trip.
Birders: note that puffins are not guaranteed beyond early August (viewing is best from May to July); terns (May to September) are pretty aggressive in July, when their chicks begin to be active. Take care walking around cliff edges.
To soak up Grímsey's Arctic Circle relaxation and fresh air, two places offer accommodation. There’s a small campground (800kr per person) by the community centre with very basic facilities – inquire at the town's shop.