The Church of Agios Ioannis Kastri or St.John on the Castle church is located near Agios Ioannis Cove beach. The church is famous as the location of the famous wedding scene from the movie Mamma Mia and is one of the most photographed attractions in Skopelos. The church is situated on top of a picturesque rocky cliff, and there are about 110 steps to walk up to the church. Public bus services run only till Glossa, and cars are the best option to reach the church.
The interior of the church has a few icons and an altar. The church is not wheelchair accessible.