THE LAVA TUNNEL

The Lava Tunnel – Raufarhólshellir, Underground Volcanic Landscapes & Lava Formations

The Lava Tunnel, known as Raufarhólshellir, is one of Iceland’s best-known lava caves and a remarkable place to experience the inside of a volcanic eruption. Located within easy reach of Reykjavík and the South Iceland route, it offers visitors the rare chance to walk through a lava tube carved by molten rock more than 5,000 years ago.

Formed during the Leitahraun eruption around 5,200 years ago, Raufarhólshellir reveals the hidden path once taken by flowing lava beneath a cooling crust. Inside the tunnel, changing mineral colors, sculpted walls and dramatic ceiling openings show the powerful geological forces that shaped this underground world. The cave is impressive in scale, with wide open passages and high ceilings that make the experience feel both dramatic and accessible.

Near the entrance, collapsed sections in the roof create natural columns of light that change with the weather and season. In winter, ice formations gather in the cooler outer chambers, adding another striking layer to the cave’s appearance. In the standard visitor section, pathways and lighting help make the experience more comfortable while still preserving the raw atmosphere of the tunnel.

An Underground Contrast to Mount Hengill & Hveradalir

The Lava Tunnel adds a different dimension to a visit in the wider Hveradalir area. While Mount Hengill offers broad volcanic scenery, geothermal landscapes and panoramic hiking, Raufarhólshellir takes visitors beneath the surface to see the inner structure of an ancient eruption. Together with Hveradalir’s mineral-rich mud baths, these places create a rich South Iceland experience that combines geology, exploration and relaxation.

Why Visit The Lava Tunnel

For visitors interested in Iceland’s volcanic nature, The Lava Tunnel is one of the most accessible and visually memorable cave experiences in the country. It works especially well as part of a day that includes geothermal landscapes, mountain viewpoints and nearby natural attractions, giving you both the wide open scenery above ground and the dramatic volcanic architecture hidden below it.

• Location: Raufarhólshellir, around 30 minutes from Reykjavík
• Highlights: lava tube formations, skylights, mineral colors and winter ice formations
• Geological origin: formed during the Leitahraun eruption around 5,200 years ago
• Best combined with: Mud Bath and Hveradalir Geothermal Area