Thiene Cathedral replaced a previous church of the Assumption which apparently dated from before 1166. Construction was completed by 1314. It was rebuilt in 1625, and was substantially altered in the late 18th century by architect Ottone Calderari. The dome was not added till the 1930s. The nave ceiling is decorated with 15 paintings by Baroque Venetian painters, including Giulio Carpioni and Giovanni Battista Pittoni.
Next to the church is the tall obelisk-like bell tower, designed by Sebastiano Serlio, beyond which is the Church of the Rosary built in 1685 in a staid Baroque style. This church contains stucco and painted decorations by the local artists Ballante (1657-1729) and Valentino Bassi (17th century). The main altarpiece was painted in 1590 by Matteo Grazioli. The painting of the Annunciation in the north aisle was painted by the school of Alessandro Maganza (1509-1589). There are some ancient frescos, restored in the 1700s, of the 'Madonna delle Grazie' and a marble statue of Saint Joseph by Orazio Marinali.
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.