The establishment of the first fort in Igoumenitsa dates back to Late Roman times and is probably related to the Late Roman – Early Christian settlement (2nd – 6th cent. AD) excavated in Ladochori plain in the cove of Igoumenitsa bay. From the abandonment of this settlement in the 6th century until the middle of the 13th century, when Thesprotia was incorporated in the territory of Despotate of Epirus, remains unknown if and how habitation continued in the area of the modern city. The castle is connected with the history of the town of Igoumenitsa from 15th century onwards, when the city was a commercial station and one of the outposts of Venice in western Greece, until its final conquest by the Ottomans in 1540. In 1685, the Turkish fort was blown up by the Venetian fleet led by admiral Morosini and a century later was partially rebuilt after its capture by Ali Pasha of Ioannina.
The Castle of Igoumenitsa has a trapezoidal ground plan and covers an area of about 6.000 sq.m. The walls of the castle have been repaired various times. The fortification wall in its current form is built with rubble and mortar. It is preserved to a height of about 6m and has average thickness of 2m. Along its best preserved south side there are arched cannon holes. All sides of the fortification are strengthened by rectangular towers, which communicate with the interior of the castle through arched gates. The northeast side was protected with internal partition wall and operated as a citadel. The main gate of the castle was probably at the eastern side and was protected by two rectangular towers.