Located in the Thingvellir National Park, this glacial lagoon is one of the top dive sites in the world.
Someone once described diving in super clear water to me as feeling like flying. It is so crystal clear you almost feel like you are suspended in air.
The Silfra fissure is important for two reasons. It is an actual crack between the North American and Eurasian continents, so you can dive right between the two continental plates. They drift apart by 2cm each year.
Secondly, the visibility underwater is over 100m. It is so clear that there are very few places in the world like it.
The water is super cold (2 to 4°C year round) and comes from the Langjökull glacier. It is filtered through underground lava rock for 30 to 100 years before reaching the north end of Thingvellir lake.
It is so clean, you can drink it.
There are very few fish in Silfra, instead there is lots of green "troll's hair" and other algaes which create amazing colours under the water.
The Thingvellir National Park has been declared a UNESCO World Heritage Site, so it is well worth a visit - even if you aren't into diving.
If you fancy taking a dive tour of Silfra (let's be honest - after seeing these pictures, who doesn't?) you can book a session here.