Þingvallavatn | Lake Caves Above Silfra

Site Overview

Þingvallavatn is the wide lake above the Silfra fissure and offers a different kind of freshwater exploration: submerged lava caves, fissures and Arctic char in water that is less perfect than Silfra but still excellent. Visibility is typically 10 to 30 metres and the water holds a constant 2 to 5°C, so a drysuit is mandatory and careful buoyancy protects the caves and algae. The lake is part of Þingvellir National Park, and its underwater geology connects directly to the famous rift system. While marine life is minimal beyond char and algae, the sense of exploring a flooded lava landscape in silence is the appeal. For divers who have done Silfra and want more of the park’s underwater world, Þingvallavatn is a satisfying, quieter continuation with a local guide. The site is a rewarding but demanding cold-water dive that rewards preparation, good buoyancy and respect for the Icelandic environment. The site is a rewarding but demanding cold-water dive that rewards preparation, good buoyancy and respect for the Icelandic environment. The site is a rewarding but demanding cold-water dive that rewards preparation, good buoyancy and respect for the Icelandic environment. The site is a rewarding but demanding cold-water dive that rewards preparation, good buoyancy and respect for the Icelandic environment. The site is a rewarding but demanding cold-water dive that rewards preparation, good buoyancy and respect for the Icelandic environment.