The Split Mound Cave - The Lava Tunnel

Useful Information

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. (N.63º 56.407 / W. 021º 23.742)
Open: All year daily 9-17.
Evening tours: OCT to 15-APR daily 21.
JUN to AUG daily 18, 20.
Standard: every hour on the hour.
Lava Falls Adventure: only by reservation.
Fee: Standard: Adults ISK 7,400, Children (12-15) 3,700, Children (3-11) free, Children (0-2) not allowed.
Pre booked: Adults ISK 6,900, Children (12-15) 3,400.
Lava Falls Adventure: Adults ISK 19,900, Children (12-15) 9,950, Children (0-11) not allowed.
Classification: Speleologylava tube, SpeleologyIce cave.
Light: LightIncandescent Electric Light System LightColoured Light
Dimension: T=0-4 °C. L=1,360m
Guided tours: Standard: D=1 h.
Lava Falls Adventure: D=4 h.
Photography: allowed
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: contact
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.



This lava tube is about 1,360 m long, 10-30 m wide and up to 10 m high. The average thickness of the ceiling is about 12 meters. At one point, the road 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 until a few years ago. Now it is a show cave with electric light (unfortunately coloured) and paved trails and operated under the name The Lava Tunnel. You can go there and take one of the comfortable one-hour tours. But the operator who once organized the cave trekking tours into the cave still offers them, they are called Lava Falls Adventure Tours now. We recommend checking both websites and pre-book online which is much cheaper.