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:Kakesbeck is one of the largest medieval fortifications in Münsterland and the oldest castle in Lüdinghausen. The imposingly grown complex originated in 1120 as a motte, a small hilltop tower castle. After numerous changes of ownership, the castle was extended onto two islands, but it was not until the 14th century that it underwent significant alterations and extensions under the von Oer family. The estate experienced its heyday in the middle of the 18th century, when it covered an area of almost one square kilometre and consisted of five further outer castles in addition to the core castle, which were secured by ramparts and moats.
The well-maintained condition of the castle today is thanks to the late Wilfried Grewing, the former lord of the castle. The foundation named after him has been particularly committed to preserving the property since 2020.