St. Lars is a church in ruins. The choir, which is the oldest part of the building, probably dates from the 12th century. The church has similarities with Russian sacred architecture.
The Visby cathedral was originally built as a catholic cathedral in the late 12th century. It was built for German traders that frequented Visby and financed by the tax that they were required to pay. Today, it is the only medieval church still in use in Visby, the rest being preserved as ruins. After the Reformation, the church was made the seat of the diocese of Visby under the Church of Sweden.
The current church was founded in c. 1280. It has three portals, two of which are in Gothic style and one, the oldest, which is still in the Romanesque tradition. There are also Gothic windows with still extant stained glass from c. 1280 in the apse and the south façade, one of only a few instances of preserved medieval stained glass in Sweden in situ.