The Round Tower and Witch's Stone are impressive reminders of Antrim’s ancient monastic settlement. The tower was built around the 10th century as a bell-tower for protection from raiders and is known locally as The Steeple. It is 28 metres tall and is one of the finest of its kind in Ireland. The monastic site was burned in 1147.
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.