Potholes

About

IMPORTANT Information:
After a snowy winter and significant rainfall, there is a risk of high water flow. The water levels can change from hour to hour due to hydroelectric power production. This can create dangerous situations for swimmers.
Everyone is therefore urged to be cautious and respect the posted signs!  You can see a video about how quickly the water level can rise

The Potholes in Nissedal

This incredible natural phenomenon is located in the southernmost part of Nissedal municipality, near Reinfoss, about 10 km from Telemarksvegen.

The potholes are round or elongated depressions carved into solid rock, formed by meltwater during the Ice Age. Over countless years, the Fyresåna river swirled with stones and gravel, gradually shaping the riverbed—later regulated for hydroelectric power. Before development, the kettles were a well-kept secret hidden beneath the water. They only became visible when much of the river was diverted into pipes for electricity production.

A Popular Swimming Spot

Here, you experience nature’s own summer park. The potholes have long been a favorite local swimming area and can feel almost like natural hot tubs. The area stretches about 300 meters, featuring warm pools and natural rock slides. They’re located in a narrow valley flanked by rock walls, where the sun shines directly in.

For years, the site was a hidden gem. That changed dramatically after a full-page feature in Aftenposten spotlighted the spectacular rock formations. The kettles were also named "Swim Spot of the Year" in 1999 by NRK Telemark, Vestfold, and Buskerud.

Water Levels

Å Energi warns that water levels may change by the hour. Swimming and visiting the area are at your own risk. Neither Visit Telemark nor Nissedal Municipality has current information on water conditions.

Protect This Natural Treasure

The area is extremely vulnerable. Do not make fires on the bedrock, as this could cause the rock to crack. Be environmentally conscious and do not leave trash behind.

Access

A new parking lot has been established just past the Dynjanfoss power station (payment by Vipps or cash). Alternatively, you can drive in past a toll barrier.

Bicycles are allowed, but getting them past the gate can be tricky. If you choose to walk, you can take a shortcut under the old timber chute (walking on top of the chute is prohibited), or take the road around.
Note: the path under the chute is not well-marked. It passes through uneven and challenging terrain and is not suitable for young children, strollers, etc. Wear sturdy footwear—hiking boots or strong sneakers are recommended.

Distances from Dynjanfoss power station to the Giant’s Kettles:

• Approx. 7 km by bicycle
• Approx. 2 km on foot via the timber chute (turn right immediately after the bridge by the power station)