Collegiate Church of the Holy Cross and St. Bartholomew is one of Ostrów Tumski's most beautiful and iconic structures, thanks to a 70m steeple and impressive entry staircase, this curious sanctuary is actually two churches in one. Split over two levels, the building comprises the shorter windows of the Church of St. Bartholomew beneath the soaring windows of the upper level Church of the Holy Cross. The first two-storey church in Silesia, and one of only a few in all of Europe, the church was completed in 1295 as an act of reconciliation ending a long dispute between Duke Henry IV and Bishop Thomas II. For centuries the sarcophagus of Henry IV was housed in the upper Church of the Holy Cross, however today it can be seen on display in the National Museum. Standing outside the church is a large sculpture of John of Nepomuk dating from 1732.
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.