Jätturn, Nature reserve in Smedjebacken Municipality, Sweden.

Jätturn is a nature reserve in Smedjebacken Municipality featuring dense forests, open meadows, and rocky formations. The landscape combines several different natural habitats that together show what the Swedish countryside looks like in this region.

Jätturn Nature Reserve was established in 1961 and enlarged in 1986. It is part of the European Natura 2000 network. The Jätturn Cave, a protected ancient monument (RAÄ Norrbärke 89:1), was described as early as 1757 by Abraham Hülphers, who illustrated its three limestone openings.

The cave's triangular opening gave it the name Jättunkyrkan, the Giant's Church. Its walls carry initials with dates, the oldest from 1688, 1777 and 1783. Tradition holds that Engelbrekt, Sten Sture the Elder and Queen Christina visited the cave.

The reserve has marked hiking trails open throughout the year for nature walks and birdwatching. Visitors should prepare for varied terrain and changing weather conditions when exploring.

On the south side of Lake Jätturn, the limestone wall holds Jätturngrottan, a cave whose triangular opening is 2 metres wide and 1.5 metres high. Inside, initials carved with dates go back to 1688, 1777 and 1783. Tradition holds that Engelbrekt, Sten Sture the Elder and Queen Christina visited the cave.