The Castle of Osma is a medieval castle which seems to have been built in the 10th century. It was built in stone, although Count Gonzalo Tello used some Roman structures and materials which belonged to a small Christian fortress.
The castle is divided into three walled enclosures which can be easily distinguished. Nowadays you can see the ruins of this fortress which adapts perfectly to the rocky hill between the Ucero and Abión rivers, near the famous Roman city of Uxama. It was used mainly as a defensive structure located in the natural passageway to this valley and the City of Osma. Some of the walls of the main enclosure are still standing which help to make out the floor plan and you can still see its Keep, remains of other towers, the access gate and a small door. There are also remains of the other two enclosures that improved the castle’s protection. On the outer wall that goes down the hillside, you can see the Water Tower (Torre del Agua) that is located near the river.
The Castle of Osma has experienced many battles from its first reconquest in 912 all the way up to the last in 1088, and in the 15th century, it belonged to the bishop of Osma.
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.