The late-classicism style church was designed by M. Schons, chief architect of the Livonian Province. The master carpenter was Johann Karl Otto, a resident of Võru. The church was completed in 1804 and named the Greatmartyr Catherine’s Church in honour of Catherine II. The building has a simple rectangular ground planning, a sturdy western spire, a cupola-like ridge roof on the high tambour and arched windows in sham niches.
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.