Castillo de Doña Blanca is a tower built in the 15th or 16th century to watch the Cádiz bay. It is named after lady Blanca de Borbón, who was imprisoned there.
The tower is built to the archaeological area. The remains of walls, necrópolis and parts of houses date from the eighth to the third century BC and were built by the Phoenicians. It is considered an ancient city with a significant development and urban planning, which shows the great power of this port city. The first traces of occupation in the mountains and around date back to the Copper Age.
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.