In a nutshell
- Silfra is the rift between two continents at Þingvellir National Park, 47 km northeast of Reykjavík on Route 36.[1]
- The meltwater you float in stays 2°C to 4°C year round and never freezes, because fresh water keeps filling the fissure.[2]
- The Thingvellir freedive runs 3 hours with a live guide in English and Icelandic, in a group limited to 6 participants.[3]
- Reserve now and pay later, with free cancellation up to 24 hours in advance for a full refund on the guided freedive.[3]
- The Reykjavík Silfra snorkeling tour from this site runs 3 - 5.5 hours from US$137 and is limited to 6 participants.[4]
| Snorkeling | Freediving | Scuba diving | |
|---|---|---|---|
| From | from US$137[4] | from US$223[3] | from US$275[5] |
| Duration | 3 - 5.5 hours[4] | 3 hours[3] | 4 - 6 hours[5] |
| Group size | Limited to 6 participants[4] | Limited to 6 participants[3] | Limited to 3 participants[5] |
| Reviews | 4.71 from 2,142 reviews[4] | 4.83 from 40 reviews[3] | 4.49 from 75 reviews[5] |
| Guide | Live tour guide in English[4] | Live tour guide English and Icelandic[3] | Live tour guide in English[5] |
| Cancellation | Free up to 24 hours ahead[4] | Free up to 24 hours ahead[3] | Free up to 24 hours ahead[5] |
The water is therefore extremely pure by the time it reaches the north end of Thingvellir lake and it allows for underwater visibility of over 100 meters in Silfra.
Our verdict on the guided Silfra freedive
Before reserving
What Silfra freediving means in practice
Silfra is a crack in the ground where two continents pull apart, flooded with glacial meltwater so clear that it looks like a swimming pool with a lava floor. Freediving here means one breath at a time. You float, tip down, and drift with the slow current instead of carrying a tank and breathing through a regulator. It is closer to floating over a landscape than to sport diving.
The guided version is a short, structured outing rather than a long expedition. A guide stays with you the whole way, keeps the group small, and runs the plan so you can concentrate on your breathing and on what is happening under you. You do not need to be an athlete. You do need to be calm in cold water, happy to put your face in, and able to swim.
What you remember afterwards is not speed or depth. It is the quiet, and the way two rock walls slide past on either side, one belonging to North America and one to Eurasia, with a green glow on the rocks below and blue haze ahead. Guests often surface laughing at how silent it was down there.
Where Silfra sits and why the water looks unreal
Silfra sits inside Þingvellir National Park, 47 km northeast of Reykjavík on Route 36.[1] The park was added to UNESCO's World Heritage List in 2004.[7] The lake beside the fissure, Þingvallavatn, covers 84 square kilometres and has a greatest depth of 114 metres.[8] It is protected ground, and a busy one, with walking paths, car parks and a small church by the water.
The water in the fissure has had a long journey to get there. Glacial meltwater filters through porous underground lava for 30-100 years before it reaches the spring that feeds into Silfra.[2] That filtering leaves it so pure that the fissure allows for underwater visibility of over 100 meters.[2] Temperature barely moves either: it stays 2°C to 4°C year round and never freezes, because fresh water is constantly filling the fissure.[2]
On a calm day you can stand at the top of the steps and see the far end of the fissure through the water, which is a strange thing to be able to do. The blue shifts with the light and the weather rather than with the season, so two visits in the same week can look quite different.
Freedivers drifting over the green troll hair in Silfra's filtered water.
What the guided freedive tour involves
The most direct option is the Thingvellir Silfra freedive listing, a guided adventure from US$223 per person.[3] It runs 3 hours, with a live tour guide who speaks English and Icelandic, and the group is limited to 6 participants.[3] Starting times vary, so check availability for the slot that fits your drive out from Reykjavík. You can reserve now and pay later, and free cancellation runs up to 24 hours in advance for a full refund.[3]
A guided format matters more here than on a warm-water reef. With a small group the guide can watch every diver, set the pace to the least confident person, and keep the line moving with the current instead of against it. Ask before you get in about the route, the exit point and what happens if you want to stop early.
Pack the way you would for any cold day outdoors: a warm base layer, a hat, gloves for the wait, dry clothes to change into, and a strap for glasses if you wear them. Leave loose jewellery and anything that can fall out of a pocket behind, and keep your bag small and tidy.
Freediving, snorkeling or scuba diving at Silfra
Three ways in, one stretch of water. Snorkeling keeps you on the surface looking down, and the Reykjavík tour on this site runs 3 - 5.5 hours and starts from US$137.[4] Freediving takes the same drift on a held breath, from US$223, in a group limited to 6 participants.[3] Scuba diving follows the walls on a tank, from US$275,[5] and it is the one with a formal bar: to dive Silfra you are required to have either a drysuit diver certification or drysuit dive experience.[9]
Snorkeling is the version that asks least of you, but it still asks for real comfort in the water. For snorkelling at Silfra, participants must be at least 12 years old, at least 150 cm tall, and able to swim and be comfortable in water, and life jackets and swimming aids are not permitted.[6] If you have never put your face into cold water, that last rule is worth taking seriously before you book.
Freediving sits between the two. You get the closeness and the quiet of diving without the equipment, and more time under the surface than a snorkeler who stays flat on top of it. Whichever version you choose, the water is the same water and the walls are the same walls.
100+ meters
Silfra's meltwater is filtered clean by the time it reaches the fissure, so the water allows underwater visibility of over 100 meters.[2]
Underwater: troll hair, lava and blue light
There is not much living down there, and what does live there is small and bright. The marine life in Silfra consists mostly of bright green troll hair and different types of algae,[2] which is what gives the shallows their green glow while the deeper water stays blue.
The scale of the place surprises most first-timers. Silfra reaches depths of up to 200 feet (60 meters) in its deepest sections, though most snorkeling takes place near the surface.[10] Freedivers and snorkelers stay in the upper part, where the light is strongest and the walls close in on both sides.
The rock itself is the other attraction: black and grey lava, cracked, rounded and piled in slabs, with pale sand in the gaps between boulders. The plates that made it are still moving at Þingvellir, where the land between them subsides. Away from the plate boundaries the activity is fairly constant at about two centimetres a year, while in the rift zones stress builds over long periods and is released in bursts.[11]
How to plan your day at Þingvellir
The drive out is simple. Þingvellir National Park is 47 km northeast of Reykjavík on Route 36.[1] It is a popular stop, receiving approximately 1.5 million visitors each year,[12] so arriving early in the morning or late in the afternoon makes a real difference to the paths and the parking.
Dress for two different climates. The air can be mild, windy, wet or snowy, while the water stays 2°C to 4°C year round.[2] Wool next to the skin, a warm hat, gloves for the walk between the car park and the water, and a full change of clothes in a dry bag are the usual list. Freediving Silfra in Iceland means the cold is the thing you plan around, not the depth.
Many people pair the water with the Golden Circle, since the sights sit along the same road. As one example, the Golden Circle and Silfra snorkeling day runs 10 hours from US$298 with pickup included.[13] If you are freediving instead, you can drive the same loop afterwards at your own pace and stop where you like.
Rules, safety and what to expect in the water
The rules come from the site rather than from the tour company, and they are worth reading before you pay. For snorkelling at Silfra, participants must be at least 12 years old and at least 150 cm tall, must be able to swim, and must be comfortable in water, and life jackets and swimming aids are not permitted.[6]
Cold water is the real subject of the day. Your face will sting for the first few seconds and your breathing will want to speed up. Slow it down deliberately, look at the rock rather than at the surface, and let your suit do its work. Cold also drains energy quickly, so a short guided outing with a small group is plenty for a first visit.
Scuba diving has its own requirement: to dive Silfra you are required to have either a drysuit diver certification or drysuit dive experience.[9] Whichever way you go into the water, be honest about how you cope with cold and how long you can hold a breath comfortably, and tell your guide if anything changes while you are in the fissure.
From-prices per person for Silfra tours
From-prices per person: Reykjavík snorkeling,[4] Thingvellir freedive,[3] Thingvellir dive,[5] Golden Circle with Silfra snorkeling.[13]
What a Silfra water tour costs, from-prices in US dollars
From-prices per person for the tour listings below, in US dollars:[3][4][5][13][14]
When to book and when to go
How a Silfra freedive runs
Pick your date
Check availability for starting times, then reserve now and pay later if you would rather not pay today.[3]
Sort your layers
Cold air above the surface, cold water below it. Wool next to the skin, a hat for the wait, and dry clothes in a bag for afterwards.
Meet your guide
A live guide speaks English and Icelandic on the freedive, so ask about the route, the current and the exit before you get in.[3]
Float the fissure
You drift with the current between two continents, over bright green troll hair and cracked lava, in water you can see straight through.
Warm up after
Get out of the wet gear quickly, take something hot to drink, and walk the Þingvellir paths while your hair dries.
Ready to float between two continents on a guided Silfra freedive?
from US$138Reserve now & pay later
