Korppoo Church is a 15th-century medieval single-nave grey stone church, apparently dedicated to Saint Michael, located in the middle of Korppoo's main island, Kyrklandet. At the west end of the church rises a tower almost twenty metres high, which originally had five floors. The church burned badly as a result of a lightning strike in 1709 and 1834. However, recent research agrees that the church was largely completed in the first half of the 15th century.
Perhaps the most special detail of the medieval interior is our country's only surviving shell gallery railing, which is now in its original place between the nave and the shell. Finland's oldest wooden sculpture, the Korppoo Madonna from the Rhineland, which originally belonged to the church from the 1220s, is now housed in the National Museum. However, there are other medieval sculptures in the church, such as Saint George, Saint Michael, Saint Olaf, the Madonna and Child and sculptures depicting Catherine of Alexandria. The 15 sculptures in the altar cabinet are Swedish works from the 15th century.