Iceland is part of the Schengen Agreement, which means a hassle-free passage for most Europeans (with a identity card of course; validity of at least four months from your date of arrival). If you’re from the US, Australia, New Zealand, Japan or China you can also travel to Iceland without a visa for up to three months. Other nationalities need a visa; check the embassy for checking up on your personal situation.
Furthermore, keep note that:
– Dry suit is a must (if you have no experience; buoyancy will be different!)
– A Hyperbaric chamber is located at Landspitali Fossvogi
– Iceland is quite expensive
– Infrastructure is great (electricity (European plugs), ATMs, Wi-Fi, etc.
– There is virtually no crime