Tucked away on the peaceful Kuusisto Island near Kaarina, just outside Turku, Kuusiston Piispanlinna is a fascinating medieval castle ruin with a rich history. Originally built in the 1300s, this bishop's castle served as a residence for the bishops of Turku and played an important role in Finnish religious and political life until it was ordered to be demolished during the Reformation in the 1500s.

Today, the atmospheric ruins are open for visitors to explore freely. Surrounded by coastal nature, meadows, and forests, it’s a perfect place to combine a little history with a scenic walk. There are marked trails in the area and a viewing platform offering beautiful views of the archipelago. In summer, it’s also a lovely picnic spot, and occasional cultural events or performances are held on-site.

You can reach Kuusisto by car or bike from Turku in about 30 minutes, and there's parking nearby. Whether you're a history fan or just enjoy peaceful coastal views, this site is well worth the detour. Best of all, it's free to visit.