The dogal Republic of Venice purchased the area of Butrint including Corfu from the Angevins in 1386; however, the Venetian merchants were principally interested in Corfu and Buthrotum once again declined. The Venetians began to invest in Butrint in the late 15th century, which seems a likely date for the Triangular Fortress construction. Musket ports opened at both ground level and along the parapet walk. Vaulted storerooms inside the fort carried artillery platforms above to train cannon on the approach to Butrint up the Vivari Channel. In 1798, however, the fortress was slighted by General Chabot, the commander of the garrison of the French dependency of Corfu.
Triangular Fortress takes the form of an irregular triangle with a tower at each point. Originally, it stood on an island in a pre-canalised river mouth, protected by an outer siege work or ravelin (a crescent-shaped defensive wall).The keystone of one the interior buildings bears a relief of the Lion of St. Mark, the symbol of the Republic of Venice.
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.