St. Andreas Castle is a privately owned castle located in Cham, in the Canton of Zug. The castle hill has been used since at least 400 AD, based on Roman artifacts found there. The site of the neighboring chapel has been used for religious ceremonies since the Roman era. During the 8th century the chapel site was used by a 'holy bishop without a name' for Christian services.
Today the castle and chapel are located on a 67,000 square metres private park. While the castle is privately owned, the grounds are opened to the public twice a year.
References:Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.