The majority of the remaining St Mary's Church dates from the 15th century with some features retained from the 13th century. There is believed to have been a church on the site since Norman times, and Gerald of Wales is counted as the earliest Rector of Tenby.
The 13th century chancel has a 'wagon' roof and the panelled ceiling has 75 bosses carved in a variety of designs including foliage, grotesques, fishes, a mermaid, and a green man, as well as the figure of Jesus surrounded by the four Apostles. St. Thomas' Chapel was added in the mid-15th Century, and the St. Nicholas Chapel was added c. 1485. The spire is also a 15th-century addition. Inside the church is a 15th-century font and a 15th-century bell, cast with the letters Sancta Anna.
The tower is positioned to one side of the chancel and dates from the late 13th century. The first floor served as a chapel, and still has a stone altar and piscina in place.
The church has two fonts, one dating from the 15th century and another late Gothic example from the 19th century.
The church contains several memorials, including the tombs of Thomas and John White, both Mayors of Tenby in the fifteenth century. Thomas White was famous for hiding a young Henry Tudor from King Richard III.
In the churchyard, 20 metres west of the church, are the remains of what is believed to be a late 15th-century choir school or college. The wall includes a pointed arched doorway.
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.