In addition to the profusion of wrecks, the submarine scenery and wildlife are major attractions for sport divers and underwater photographers. More and more divers are discovering that, quite apart from the fascinating wreck sites, Shetland's profusion of underwater wildlife is truly astonishing, one of the richest marine environments around the British Isles.
Shetland’s coastline extends to 2,702 kilometres (1,697 miles) and Gordon Ridley, in Dive Scotland Volume III, estimates that it offers 405 geos (coves), 351 caves, 246 bays and firths, 205 skerries, 190 stacks, 158 natural arches and at least seven subterranean passages. There’s plenty to keep the keenest scuba enthusiast busy for a lifetime!
The variety of diving experiences is a big draw - Shetland has everything from historic wrecks (like the 18th Century Swedish East Indiaman and WWI steamship Gwladmena - both in Lerwick Harbour) to modern trawlers and the 1993 wreck of the huge tanker Braer; from sea cliffs and gullies teeming with colours and life to offshore pinnacles and reefs.
The shape of Shetland means that you can dive on almost any day of the year - there's always somewhere sheltered, with deep water close inshore.
The long hours of summer daylight are an added bonus, allowing you to pack more diving time into a week's stay than would be possible further south.
The water is chilly, but nothing like as cold as most other places on this latitude. In late summer the sea temperature gets up to around 13°-14°C, dropping to 5°C or 6°C in midwinter.