The fortified-looking church of Santa María of Baiona, with a Ogival Romanesque style, was built in the 13th century and had the category of collegiate church from 1482 to 1850.
It is divide up in three naves with their respective rectangular apses. The main nave resembles the Cistercian style of Santa María de Oia monastery. Two buttresses flanked the front door in the main façade: three pairs of columns, flat tympanum and archivolts. Windows are Romanesque; there is a marvellous Romanesque rose window up in the main façade. In 1841 several crosses of different styles formerly placed around the village were moved to the portico.
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.