The geological name for these circular depressions is 'moulin potholes', formed by the erosion of bedrock by subglacial meltwater streams.
The depth of these kettles can reach several meters, with some deep enough to allow for diving during periods of high water levels.
The site was historically utilized by timber floaters to guide logs down the river system before the era of modern road transport.
The bedrock surrounding the pools is part of the Telemark supracrustal rocks, which are among the oldest in Norway.
Jettegrytene (Giants' Kettles) in Nissedal consists of a series of natural circular rock pools carved into the riverbed of the Fyreselv river. These formations were created during the last ice age by stones being swirled by pressurized meltwater. The site features smooth, polished granite basins of varying depths that function as natural swimming pools. The surrounding terrain is characterized by large, sloped, open rock faces that serve as sunbathing areas. The river water flowing through these basins is typically clear and refreshing. The site is a popular destination for wild swimming and geological exploration in the Telemark region. Visitors reach the pools by traversing the open rock formations adjacent to the riverbank.
From the elevated rock ridges overlooking the main series of interconnected basins.
Wear water shoes or sandals with grip, as the granite rock can be extremely slippery when wet.
Bring a waterproof bag for electronics, as there are no dry storage facilities near the water.
Check water levels before swimming, as heavy rainfall upstream can significantly increase current strength.
Avoid entering the water if there are signs of recent heavy rain or if the water level appears to be covering the primary sunbathing rocks, as strong currents can be dangerous.
The site is accessible only during the snow-free season, typically late spring through early autumn.
