Halki Castle is located on the hill of St. Nicholas over the old village of Halki. It was built by the Knights of St. John in the 14th-15th century over the ancient Hellenistic citadel. From there they were able to control the sea routes, the harbor and the Trachean peninsula. Inside the castle are the ruins of the medieval church of St. Nicholas. At the gate the emblem of the Grand Master of the knights Pierre d’Aubusson (1476-1503) is engraved.
Today, the castle is accessed through a paved path from where the view is just fascinating. The back side of the hill is rough and its slopes lead to the sea. At the foot of the castle, there are three small chapels dedicated to Virgin Mary, to Saint Nicolas, and to the Holy Trinity.
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.