Raufarhólshellir

The Split Mound Cave - The Lava Tunnel

Useful Information

photography — Raufarhólshellir, Iceland. Public Domain.

Location:	From Reykjavik east on road #1, after 18 km turn right on road #39 for 12 km. At the main road to Thorlakshofn, Hveragerdi. East of the road, where the road starts descending in the South. (63.9402409, -21.3971824)
Open:	All year daily 9-17. Evening tours: 15-OCT to 15-APR select days 21. JUN to AUG daily 18, 20. Standard: every hour on the hour. Lava Falls Adventure: only by reservation. Online booking. [2025]
Fee:	Standard: Adults ISK 8,400, Children (6-15) ISK 4,200, Children (3-5) free. Lava Falls Adventure: Adults ISK 25,900, Children (12-15) ISK 12,950. [2025]
Classification:	lava tube, Ice cave.
Light:	Incandescent Coloured Light
Dimension:	L=1,360 m, T=0-4 °C.
Guided tours:	Standard: D=1 h, MinAge=3. Lava Falls Adventure: D=4 h, MinAge=12. 20,000/a [2015]
Photography:	allowed
Accessibility:
Bibliography:
Address:	The Lava Tunnel, Klettagarðar 12, 104 Reykjavík, Tel: +354-519-1616. Tickets: Tel: +354-760-1000. Extreme Iceland, Gylfaflöt 20, 112 Reykjavik, Iceland, Tel: +354-565-9320, Mobile: +354-898-5448. E-mail:
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then. Please check rates and details directly with the companies in question if you need more recent info.

History

1971	cave first explored and surveyed by the Shepton Mallet Caving Club.
2016	cave gated to avoid vandalism and garbage accumulation, developed as a show cave.
2017	cave opened as a show cave.

Description

Raufarhólshellir is a lava tube, which is about 1,360 m long, 10-30 m wide and up to 10 m high. It is currently the 4th longest lava tube in Iceland. The average thickness of the ceiling is about 12 m. At one point, the highway 39 crosses the cave, and the ceiling is much thinner. The traffic continually destroys the lava, and so the ceiling becomes thinner and thinner. Probably it will become necessary to sustain the road in the future.

The cave is an ice cave of the cold trap type. All openings are going up to the surface, so cold air flowing downwards into the cave is trapped. The cave is famous for its ice formations, but also for many lava formations. The ice exists only during winter, and while the formations are interesting and beautiful, the ice coating on the rocks makes visits during winter more dangerous.

The tube has four entrances, and it is possible to visit the cave sections by entering through one and leaving through the next. At the upper section the cave forks into three passages, which means there were originally three lava flows which joined and formed a single flow. The Leitahraun lava field in which the cave is situated was formed during a fissure eruption about 5,400 years ago. It belongs to an 11 km long crater row.

Raufarhólshellir was a natural lava tube and freely accessible until 2016. Now it is a show cave with electric light (unfortunately coloured), paved trails, and operated under the name The Lava Tunnel. You can go there and take one of the comfortable one-hour tours on the paved trails. But they still offer the more adventurous tours into the rest of the cave, they are called Lava Falls Adventure Tours now. The cave was filming location for the 2014 film Noah and the series Sense8. In June 2017, two concerts of the Secret Solstice music festival took place in the cave. The area where the cave is located is owned by the Seventh-day Adventist Church and rented to the company which operates the show cave.