Quick answer: Silfra is a fissure in Þingvellir National Park filled with very clear glacial spring water, where you can snorkel in a drysuit between the North American and Eurasian tectonic plates. Most listings set the minimum age at 12 (some tours require 14 or older), and sources put the water at around 2 to 4°C. Listings I found in 2026 range from about €138 for a three-hour tour to ISK 17,990 for a self-drive tour, but these are third-party prices, so confirm with the operator.

Last updated: November 2026. I couldn't find an official 2026 rule set, so treat age limits and prices as indicative and check your operator's terms.

What Silfra is

Silfra is a narrow rift in the Þingvellir National Park, on the Golden Circle route about an hour from Reykjavik. The water comes from the Langjökull glacier, filtering through lava rock for decades, which is why visibility can be extremely clear. It sits in the rift where the North American and Eurasian tectonic plates are pulling apart. That's why searches such as "silfra snorkeling", "silfra fissure snorkeling" and "bridge between continents" turn up together. You float between the walls of the fissure, wearing a drysuit and a mask, and the guide leads you through the route. It is not a swim in a warm lagoon. It is very cold, you're in a drysuit with a hood and thick gloves, and you spend a short time in the water, with a guide. For many visitors it is a highlight, but it isn't for everyone.

Who can do it

Age limits depend on the operator. Most listings put the minimum at 12, one Golden Circle guide says some tours require 14 or older, and another source says 14 to 16 is typical. Confirm the exact rule on your booking confirmation. Operators generally don't ask for a certification for snorkelling, but swimming ability is expected. One source notes that the fissure is deep and the route runs several hundred metres, so you do need to be comfortable in water. Height, weight and age details are often collected in advance so the right suit size is supplied. Pregnant participants are advised against snorkelling, and people with certain medical conditions, such as heart or lung problems, epilepsy or severe claustrophobia, should ask their doctor and the operator first. Tell the operator about medical conditions when you book. Operators may refuse participants who don't meet the requirements, so read the terms and cancellation policy before paying.

QuestionWhat sources say
Minimum ageUsually 12; some tours 14+ (varies by operator)
Water temperatureAbout 2 to 4°C year-round
EquipmentDrysuit and undersuit provided
SkillsSwimming ability expected; certification usually not required
PregnancyAdvised against

What it costs

Iceland - Latest circular - United Kingdom
IcelandLatest circular, valid until 9 November 2026

Prices differ a lot by operator, group size and what's included. 2026 listings on third-party sites show examples: about CHF 127.84 for a 2.5-hour tour, €138 for a three-hour tour, and ISK 17,990 for a self-drive tour where you meet the guide at the site. Those include different things, such as photos, hot drinks and transport from Reykjavik. Entrance fees to the national park, parking and the Silfra fee may be extra. Convert to pounds at current rates, and check what's included. Compare a few operators, and read recent reviews from people who have actually done it. Cheaper isn't always better: group size, guide experience, equipment quality and safety record matter. Look for operators that explain their safety procedures and cancellation rules clearly, including what happens if weather or conditions stop the tour. If the Iceland offers are not quite what you need, it is worth comparing them with the latest Aldi leaflet and the current Asda leaflet before you decide.

Practical tips

Wear warm layers under the undersuit, and bring a towel and a change of clothes for afterwards. Keep your hands warm, because they're the part of your body most exposed to the water. Don't wear contact lenses if you're prone to irritation, and ask about prescription masks. If you have long hair, tie it back. Book ahead in summer, when tours are busy. Weather affects Þingvellir, but the water temperature stays about the same all year, so winter tours are possible. In winter, daylight is short, so book a morning slot. If you also want the Golden Circle sights, plan the order of your day with your operator. Your insurance should cover water activities. Check the small print of your travel insurance, because some policies exclude snorkelling or diving, and some exclude activities in extreme cold. If you book through a UK company, check ATOL or ABTA protection for the package. If a tour is cancelled by the operator, you should get a refund or an alternative date. If you're booking via a UK platform, your Consumer Contracts Regulations rights may be limited for leisure activities booked for a specific date, as those are exempt from the 14-day cooling-off right, so read the cancellation terms carefully.

If you're worried about the cold, there are alternatives at Þingvellir and nearby. You can walk through the park for free along marked paths, visit the viewing platforms above the rift, or look at the clear water from the shore. Other Icelandic activities such as hot spring baths, whale watching from Reykjavik or glacier walks offer very different experiences with less cold-water exposure. A good operator will tell you honestly if a tour isn't right for you, and a refund policy that covers medical reasons is worth checking before you book.

One more point on photos: many tours include underwater photos in the price. Check whether they are included or an extra charge, and whether you get the files digitally. Waterproof cameras are usually fine, but read the operator's rules on equipment, since loose items can get lost in the fissure.

Frequently asked questions

What is the minimum age for Silfra snorkelling?

Most listings say 12, but some tours require 14 or older. Check your operator.

How cold is the water?

Sources put it at about 2 to 4°C all year.

Do I need to be able to swim?

Swimming ability is expected; the fissure is deep and the route is several hundred metres.

Sources