Disclaimer: This post contains affiliate links. If you click through and make a purchase, I may receive a small commission (at no additional cost to you). This helps support and run my blog. I only recommend products I personally use and love. Thank you for your support.

Snorkeling Silfra is a once-in-lifetime experience and a must-do on your Iceland itinerary. Silfra, located near the country’s capital of Reykjavík, is a unique and special place. It is the only place in the world that one can swim between two continental plates. It has some of the world’s clearest water and is absolutely stunning. It’s also very cold, maintaining a temperature of 2–4 °C (36–39 °F). Snorkeling through its quiet, crystal-like waters is unlike anything else. Here is everything you need to know before snorkeling Silfra:

The world's clearest water at Silfra

What is Silfra?

Silfra is a tectonic fissure between the North American and Eurasian plates. The rift first opened as a result of an earthquake in 1789 and continues to separate by about two centimeters per year. Tension builds between the two plates and an earthquake takes place about every ten years or so. The earthquakes have caused cracks and fissures to form within Þingvellir valley and Silfra is the deepest of those fissures. New cracks and tunnels are continually created by the shifting earth.

Why is the Water so Clear?

The water at Silfra is some of the clearest in the world, making it a great place to snorkel. Silfra is a freshwater rift and the water actually originates over 50 km north at Langjökull glacier, Iceland’s second-largest glacier. At one point in time, the glacier melt-off ran into a river that emptied into Þingvallavatn lake. A few thousand years ago, the river became blocked by lava flows from a nearby volcano.

The water then began seeping through the porous volcanic rock and moving underground, creating an aquifer. The water is slowly filtered through the rock and can take anywhere from 30 to 100 years to reach the lake, resulting in incredible clarity. It will most likely be the purest water that you ever drink or swim in. The visibility at many of the world’s most popular dive sites is usually between 10 and 30 meters. At Silfra, it extends for over 100 meters.

Snorkeling between two continental plates at Silfra

How to Visit Silfra

Silfra is easily accessible from Reykjavík but in order to enter the water, you need to be accompanied by a licensed dive organization. I chose to book my tour with DIVE.IS. DIVE.IS offers both diving and snorkeling tours. As a snorkeler, you’ll see almost as much as the divers. They operate daily tours from Reykjavík to Þingvellir National Park, the only UNESCO World Heritage Site in Iceland. Transportation via van is included in the cost and it takes about an hour to reach the park.

If you’re coming from somewhere other than Reykjavík, then you have the option of meeting at a designated point within the park. This is what I chose to do as Silfra was the last stop on my self-guided Iceland tour before returning to Reykjavík. The tour includes an experienced/ PADI certified guide, park entrance fee, all necessary equipment, a heated van to change in, photos, and cocoa and cookies. Tour cost is ISK 11.990.

Snorkeling through the waters of Thingvellir National Park

When to Visit Silfra

There really isn’t a “best” time to visit Silfra. Snorkeling Silfra can be done anytime throughout the year. Since the water travels underground it maintains a constant temperature of 2–4 °C (36–39 °F). No matter what time of year you visit, the water will always be very cold. It never freezes because freshwater is constantly filling the fissure. Something to keep in mind, though, is the outside temperature.

Exiting the water is when you will feel the coldest and I can’t imagine what it would be like during the winter months. I visited in October and although it was cold, it wasn’t unbearable. Fall and winter months are quieter and overcast days allow for beautiful reflections upon the lake’s surface. Spring and summer tend to be more crowded with tourists.

Crystal clear water at Silfra in Iceland

Preparing for the Water

My tour began with a brief overview of what the morning would entail. The near-freezing water temperatures require the use of a drysuit. One of the guides instructed us as to how to get into the provided suit and make it leakproof. For those who have never heard of a drysuit, it is a watertight shell that provides the wearer with thermal insulation.

Unlike a wetsuit, it keeps water from entering and protects the body, with the exception of the head and hands, from low water temperatures. Drysuits are far from glamorous and there’s a good chance this is the most ridiculous that you will ever look. The process of getting into a drysuit is somewhat involved and assistance from a guide is necessary. The whole process takes about 30 minutes. It’s necessary that everything fits correctly to prevent leaks, so giving the tour company your accurate height and weight in advance is important.

You’ll want to wear your warmest pair of thermals as a base layer and bring a heavy pair of socks. An insulation layer will then be zipped over your thermals. Lastly, mitts and a hood will be put on and a mask/fins provided. The only part of the body that will be exposed is your face.

A dry suit is required snorkel gear at Silfra

My Experience at Silfra

Snorkeling Silfra is a thrilling experience. I was excited but also somewhat nervous. I had never been in water that cold before. Once I was in the water, though, I was easily distracted by all the beauty around me. The crystal-clear, blue water is gorgeous. The only extreme cold I experienced was the initial getting in and exiting the water. It’s actually easier to swim in the cumbersome drysuit than one would think. It doesn’t weigh you down and will actually help you float.

Expect to be in the water for 30-40 minutes. The current will gently push you along and very little effort is required on your part. It’s normal for water to start slowly sleeping into your mitts and the less you move your hands around, the better. Your hands, along with your exposed lips, will eventually go numb. This isn’t nearly as bad as it sounds but I do recommend bringing some hot hands or a warm pair of gloves to put on afterward.

Don’t expect to see any plant or animal species on your snorkel tour as it is just too cold for most species. You’ll swim through beautiful underwater valleys and see incredible rock formations. DIVE.IS will take photos of everyone during the snorkel so a camera isn’t necessary and I actually advise against bringing one. The mitts are very bulky and you’ll have a hard time holding and operating it. If you do want to bring something to record your adventure, I recommend a GoPro. Was the experience worth it? Absolutely! I had an amazing time and the guides from DIVE.IS are great.