Sykling langs Kystriksveien langs Aldersundet i Lurøy en sommerdag Emilie Solbakken / Visit Helgeland

Aldersundet is a remarkably beautiful part of the Helgeland coast and the Coastal Highway, where a long, narrow sound meanders between the stunning island of Aldra and the high, steep mountains on the mainland where the Coastal Highway runs.

At the southern end of the Sound, you can visit Grønsvik Coastal Fort, a beautifully restored World War II coastal fort with an intriguing museum exhibit. In the north, you’ll find the small village of Tonnes, which serves as a hub for boat traffic to Kvarøy and Hestmona, home to the legendary Hestmannen mountain.

Aldersundet is located along the Coastal Road (County Road 17), just over an hour’s drive from Mo i Rana and Nesna, between Stokkvågen and Tonnes.

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Sila is a short, shallow fjord located along the Coastal Road just south of Aldersundet. It features a long beach with suitable swimming temperatures on warm summer days. The area is shallow and is best visited at high tide, preferably when the tide is rising.

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The landscape here is mostly open to the midnight sun, but if you want to be sure to see it right at midnight, it might be wise to move to higher ground. In winter, there is relatively little light pollution in the area, so you have good chances of seeing the northern lights throughout the region.

A rest stop along the Coastal Road on the south side of Aldersundet, offering a beautiful view of Aldersundet, the island of Aldra, and the islands of Lurøy and Onøy.
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This is a relatively easy mountain hike on the north side of Tonnes, where you get a stunning view of the coast and the islands in the area. It is best suited for viewing the midnight sun in the summer, or the northern lights in the late summer and early autumn.
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