Hirta, Scotland, United Kingdom

St Kilda

St Kilda is a remote archipelago in the Outer Hebrides about 64 kilometres west of the Scottish mainland and a UNESCO dual World Heritage Site for its natural and cultural value. The crystal-clear waters around Hirta, Soay, Boreray, Stac Lee and Stac an Armin offer some of the most spectacular dive sites in the United Kingdom: vertical cliffs that fall from soaring sea stacks plunge below the surface to 45 metres or more on a clean rock and sand bottom. The walls are densely covered with jewel anemones in vivid pinks and reds, plumose anemones, dead man's fingers, sponges, hydroids, pink coralline algae and kelp forests on the upper margins. Resident species include Atlantic grey seals, ballan wrasse, cuckoo wrasse, pollack, ling, conger eels, lobsters and extensive seabird populations seen at the surface. The site is famous for its unparalleled visibility, often 15 to 30 metres in summer because of the deep oceanic location, and water temperatures vary between 9 and 14 degrees Celsius. Currents are strong and weather windows demand careful planning. Dives are run from liveaboards departing the Scottish west coast.