Silfra Fissure | Thingvellir

Information

Landmark: Silfra Fissure
City: Thingvellir
Country: Iceland
Continent: Europe

Silfra Fissure, Thingvellir, Iceland, Europe

The Silfra Fissure is a geological rift located in Thingvellir National Park, Iceland, known for its exceptionally clear glacial meltwater and position between the North American and Eurasian tectonic plates.

Visual Characteristics

The fissure contains water with visibility exceeding 100 meters, maintaining a constant temperature of 2-4°C. Its walls are composed of dark basaltic lava rock. The water exhibits deep blue hues, contrasting with occasional bright green filamentous algae, sometimes referred to as "troll hair." The fissure varies in width from narrow passages where the plates are close, to wider lagoons such as Silfra Lagoon.

Location & Access Logistics

Silfra is situated within Thingvellir National Park, approximately 50 kilometers northeast of Reykjavik. Access is primarily via Route 36. A designated parking area, P5, is located near the entrance to the snorkeling and diving sites, requiring a parking fee. Public transport options are limited; most visitors arrive by private vehicle or as part of organized tour groups from Reykjavik.

Historical & Ecological Origin

Silfra is a rift valley formed by the ongoing divergence of the North American and Eurasian tectonic plates. The water filling the fissure originates as meltwater from the Langjökull glacier, which then filters through porous lava rock for an estimated 30 to 100 years before emerging into the fissure. This natural filtration process contributes to its extreme clarity.

Key Highlights & Activities

Snorkeling and diving are the primary activities, allowing visitors to experience the unique underwater environment. Participants typically wear dry suits due to the cold water temperature. Notable sections include Silfra Hall, Silfra Cathedral, and Silfra Lagoon. The unparalleled water clarity offers an exceptional visual experience.

Infrastructure & Amenities

Restroom facilities are available at the nearby P5 parking area. Natural shade is minimal at the site. Cell phone signal, including 4G and 5G, is generally reliable within Thingvellir National Park. Food vendors are not directly at the fissure; however, a visitor center with a cafe is located a short distance away within the park.

Best Time to Visit

Silfra can be visited year-round. For optimal underwater photography, visiting during midday hours provides the best light penetration into the fissure. The summer months (June-August) offer milder air temperatures, while winter (October-March) provides a unique contrast with snow and ice on the surrounding landscape. Water levels are not affected by tides.

Facts & Legends

The water in Silfra is so pure that it is potable directly from the fissure. In certain narrow sections, snorkelers and divers can simultaneously touch both the North American and Eurasian tectonic plates, effectively being between two continents. The bright green filamentous algae found in parts of the fissure are locally referred to as "troll hair."