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Hidden Earth Atlas
Geomorphic & geological oddities

Hljóðaklettar

Northeastern Region, Iceland · 66°01′30″N 16°30′25″W

Basalt formations of Hljóðaklettar beside the Jökulsá á Fjöllum river
Photo: Wikimedia Commons contributor, via Wikimedia Commons

Twisted columnar basalt formations, the roots of old volcanic craters, scattered along the Jökulsá canyon, where the wind and river echo off the rock.

Hljóðaklettar ("Echo Rocks") are the eroded cores of a row of craters that erupted under the Jökulsá á Fjöllum glacial river some 8,000 years ago. The river stripped away the softer material and left plugs of basalt jointed in every direction: fans, whorls and honeycombs rather than the neat verticals seen elsewhere. Kirkjan ("the Church") is a cave whose ceiling is a rosette of columns.

The Rauðhólar red scoria craters lie a further 2 km north on the same trail.

Why it stays quiet

Dettifoss, 30 km south, draws the coaches. Hljóðaklettar needs a gravel road and a walk, so even in July the loop trail is thinly populated.

Where it is

66.02500, -16.50700 OpenStreetMap Google Maps

Before you go

The loop is 3 km, rocky in places. Gravel road 862 is closed in winter. No services in Vesturdalur except a campsite.

Updated 2026-09-06 · Suggest a correction

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