Tonnes grotte sett innenfra og ut en sommerdag Simon Fossheim / Visit Helgeland

Tonnesgrotta is a cavernous gave situated a short but steep walk from Tonnes. The cave is almost 200 metres deep, but because of the large opening sunlight reaches all the way inside.

Key info

Degree of difficulty: Moderate. This is a short walk, but the trail is steep and uneven.
Distance one way: 500 m
Ascent one way: 70 m
Duration one way: 30 m
Wheelchair and pram friendly: No.
Trailhead: The trailhead starts at a gate on a hilltop just before Tonnes. There is space for just a few cars at the trailhead, but there is plenty of parking down by the harbour below. If you have brought your dog, you must keep it leashed on this hike.

Find the trailhead in Google Maps

Description of your adventure

Tonnesgrotta sett innenfra mot utgangen med tre personer i front. Simon Fossheim / Visit Helgeland

The trail up to the cave is short and starts by following a tractor path that circles around the mountain and into the valley, which is also a nice hiking destination. But if your goal is the cave opening, make sure you turn off this path after about 300 metres. From that fork, your trail is uneven and steep – good footwear is essential. After a steep and winding stretch, you quickly reach the cave. You also have an excellent view over the coast.

This particular cave is an exciting place for kids to explore. The cave floor is sandy and easy to walk, and there are no narrow passages in which anybody can get lost. The Tonnes grotto offers a great, safe cave adventure for young and old.

Afterwards, consider rewarding yourself to a good meal at OscarBrygga wharf. They also offer accommodation.

Respect the cave and show common sense

Tonnesgrotta is a 20,000 year old cave that has been well preserved despite its many visitors. Please help us keep it that way. Follow the principle of leaving no trace of your visit. Do not light a fire in the area, and leave no rubbish behind. Thank you for helping us preserve the natural treasures of Helgeland!

Find the trailhead in Google Maps

Thank you for respecting the local communities, and for helping us preserve the natural beauty of Helgeland!


  • Strive to leave no trace of your visit. Bring back all your rubbish, including used toilet paper, and discard it in the nearest rubbish bin.
  • Plan your toilet visits and use the opportunity when you pass a toilet. In the wilderness, make sure you are not a nuisance to others.
  • Respect the local wildlife. Keep a good distance from wildlife, livestock and birds. Keep your dog leashed.
  • Respect private property. Keep a respectful distance from houses and cabins.
  • Show good boating sense. Keep a good distance from shore and drive at a low speed, especially when you are close to anyone or anything on the water, including birds or animals. Avoid loud and disturbing engine noise. Be aware that some islands and nature reserves are important nesting sites, and that going ashore is prohibited during the nesting season.
  • Follow the Norwegian Mountain Code (Fjellvettreglene). Plan your excursion according to the weather forecast, your skills and experience.
  • Join a guided excursion or consider hiring an experienced guide, especially when you don’t have sufficient experience or knowledge to guarantee a safe trip.

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