Pirunpesä, or the Devil’s Nest, is a fascinating ice-age formation in the rocky terrain of Isovuori in the village of Ylivalli in Jalasjärvi. The area also houses a viewing tower, the Kollinluola cave, the Paimenpoika pine (named after a young shepherd who was found frozen dead by the tree one morning in the 1850s), a statue of the comedian Spede Pasanen, an outdoor toilet and a Lappish hut that is available to hikers all year round.
The area also offers a 7.5 km signposted nature trail for walkers (8.5 km by bike). The route travels between Juustoportti in Jalasjärvi and the Devil’s Nest. A shorter 1 km route runs around the area.
In the summer months, visitors can buy coffee, home-baked buns, ice cream and other refreshments from a café.
The area and the café are maintained by Ylivalli’s youth association.