Koivusaari is an island on the Ounasjoki which has an easily accessible duckboard trail where visitors can learn about some of Rovaniemi's cultural landscapes, flora, and fauna areas. There is also a floating bird-watching tower at the southern end of the trail.
The trail is dotted with various information boards that explain the surrounding nature as well as retell of the railway that temporarily passed through the island from Rovaniemi to Saarenkylä during the winter time from 1946–1951. In the summer time, sheep are pastured on the island so its not uncommon to see them when visiting.
The entrance to the island trail is a staircase that is on the left-hand side of the highway going north about 2.3km from the city centre. If traveling north on the right-hand side of the footpath from the city, you will see a set of stairs on the right after crossing the 2nd bridge which can be followed to a path underneath the bridge leading to the left-hand side of the highway. From there follow the footpath on the left-hand side of the highway back to the Koivusarri entrance which is just before the 2nd bridge. The island is just opposite of the boat docks at the marina. If there is no traffic coming, you can also simply walk across the highway just before the second bridge and you will see the steps leading down to the entrance.