Underwater & Underground
Explore the amazing ways that geothermal and volcanic activity has shaped our landscape! We will take you underwater and deep underground for the most unusual views of what happens when the ferocious forces unground meet the surface of our world.
We will first take you snorkelling through hot springs at the bottom of Lake Kleifarvatn. Lake Kleifarvatn is hidden within a stunning volcanic landscape just 30 minutes outside of Reykjavík. Don’t let the term “hot springs” fool you though. The lake is still very cold and you will put on a dry suit in order to stay warm in this remote lake.
Upon entering the lake you can see the white and yellow sulfur deposits on the lake floor. When we swim closer, you’ll begin to sense the environment around you changing as you approach the gas emanating from below the lake’s floor. We’ve heard this sensation described as similar to ‘snorkeling in a glass of Champagne’—the fact that you are snorkeling in a caldera is also impressive enough!
When back on land we will enjoy some refreshments at the shore before moving on to Seltún, a nearby high temperature geothermal area on land. In Seltún we will walk along the boiling mud pots and colorful sulfur deposits.
We will then make our way to the fantastic lava tube called Leiðarendi where you will descend into the extensive systems of lava caves. These caves, or tubes, were created during volcanic eruptions as molten lava flowed while also cooling at the surface. These tubes now form an incredible underground world and are safe for exploration. You will be surrounded by fantastically odd rock formations and your flashlight will bring the phenomenal display of colors to light.
After the lava caving tour, before going back to Reykjavik, you will visit the unique Aurora Basecamp Northern Lights Observatory and the attached Dark Park, where you will witness a lifelike simulation of the mesmerizing Northern Lights that light up the Icelandic skies in the wintertime.
Please note that our pick up is between 11:00 and 11:30, please be ready to go at 11:00.
Our Souvenirs can be purchased in your booking process by selecting them under "Extras". If the Souvenir you are looking for is not listed below please contact us or leave a comment in your booking and we will bring it on tour with us.
Humbling, Exhilarating, Moving, Inspirational!
[...] I can only say that as soon as my head entered the water and my eyes and breathing adjusted, I was in a completely different and totally magical world of wonder and breathtaking beauty! There are not enough words to explain how awesome this gorgeous place is, this hidden and unexpected wonder that lies beneath the surface and between the tectonic plates; the rifts, cliffs, the vibrant and unexpected colours, everything about beautiful Silfra was truly remarkable! We were advised that too many facial expressions were not a good idea as they allow water to enter your face mask, but I could not stop smiling!! It was something that I will remember for the rest of my life! Once we'd reluctantly dragged ourselves out of the water, we made the short walk back to the van to get changed back into our clothes, and were rewarded with hot chocolate and cookies, and very well received they were too! I would absolutely recommend this fabulous adventure to everyone, but please be mindful of the instructions they give you. You WILL need long thermal underwear for extra warmth, even though you are given a base layer for under the dry suit. You WILL need extra thermal socks (I wore 3 pairs!) and you Will need to be confident in water because this isn't just any old snorkel. For an experience of a lifetime, contact this great company and enjoy every single bit of it!
May 1st - September 30th
8 snorkelers per snorkel guide
Maximum 8 cavers per cave guide
- Long underwear
- Thick socks
- Suitable clothes for the weather of the day
- Contact lenses if you wear glasses
- Sturdy shoes
- guided snorkelling trip in lake Kleifarvatn
- all necessary snorkelling equipment
- icelandic snacks at the lake's shore
- guided cave tour
- all necessary caving equipment
- pick up and drop off in Reykjavík
- hiking shoes
- long underwear
11:00 pick up in Reykjavík
Safety requirementsParticipants must:
have read, signed, and followed directions on the online Snorkeling Medical Statement (link provided in confirmation email) PDF
have our Snorkeling Medical form signed off by a doctor if they are age 60 or older PDF
sign our liability release form at the start of the snorkeling tour PDF
be at minimum 150cm / maximum 200cm
be at minimum 45kg / maximum 120kg
fit within our dry suit size chart PDF
be at least 12 years of age on the year
be comfortable in water and be able to swim
be physically fit
be ready to wear a sometimes tight & constricting dry suit
be able to communicate in English
not be pregnant
Iceland is now open, check our news section for details dive.is/about-us/news.
You can use your government gift card with us, you simply enter the gift card code on the Checkout page.
Your bookable extras
Experience the tour
Guides on this tour
You'll go snorkeling and caving here
Frequently asked questions about our Geothermal Snorkel Tour and Lava Caving Combo
Can I pay on site?
All bookings need to be paid for in advance, due to high demand on our tours. If however a booking is made on site, the payment can be taken there either by credit/debit card or cash. Payment for souvenirs can be made on site by both card and cash transactions.
How long is the cave?
We use 2 different caves on this tour, depending on the time of year and weather/road conditions. Gjábakkahellir cave in Thingvellir is 360 meters long and Leiðarendi cave in Reykjanes is 880 meters long.
When is the best time of year to visit Iceland?
Every time of year has its own benefits. It is least crowded in spring and autumn and you will often have a full range of activities available to you, but with less people than in summer, which is of course the busiest season here in Iceland. Winter has its own beauty and should not be dismissed, although it is not for the faint hearted as the weather can get quite extreme, and you would need to be flexible with your plans as tours can end up getting cancelled due to the weather. It is however the time for Northern Lights, so pros and cons as always. Please also be aware that winter lasts much later into the year than in most countries and there is often still snow in March and April. From a dive and snorkel point of view, it makes little difference which of the seasons you visit as our groups are small and the dive sites, visibility and marine life are pretty constant through out, varying more from day to day, than from season to season. The ocean temperatures are warmest, however, in summer and fall – about 8-12°C. For our other dive sites, such as our geothermal site and some of our other inland sites, are also warmest in summer and fall, although at a lower temperature, 6-8°C. Silfra however retains a constant temperature of 2-4°C.
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