Korouoma is a 30 kilometer long fracture valley in Posio. It is a part of a fracture zone in the bedrock, which is hudreds of millions of years old. At the centre of Korouoma the fracture valley forms a gorge with cliff faces tens of metres high and extremely steep.
Small streams which cascade down the cliff faces freeze into frozen waterfalls during winter, making Korouoma the number one ice climbing destination in Finland. The fallen rocks form impressive piles to the bottom of the canyon.
The River Korojoki meanders and twists at the bottom of the canyon making it suitable for recreational fishing. The flora and fauna varies throughout the area. A 30-km-long hiking trail traverses the Korouoma area.