The Castle of Kruja is located in the southeast of the city of Kruja, at 560 m above sea level, on a rocky ridge that rises slightly from east to west. The 10-15 m high rocky ridge serves as a natural fortress for the 800 m long defensive walls of the castle, which surround an area of 2.55 hectares. The surrounding walls are reinforced with 9 circular, square and polygonal towers. In one of the towers, a row of bricks can be seen between the stone masonry, which would indicate an early construction phase, in the IV-VI centuries.
Studies show that the castle of Kruja was inhabited since the second half of the century IV BC. In the VI-VII centuries, from the castle of the late antiquity period, Kruja turns into a city. The inventory of cemeteries of the V-VI centuries outside the castle testify to the prosperity and high standard of living of this center.
At the highest point of the castle, to the north-east of the castle, there is a surveillance tower, known as Clock Tower. The 16 m high and 8 m wide tower, belongs to the XII-XIII century and served as a surveillance point. There is small rocky platform of Taslloja, in the west of the castle, as well as some water sources at the rock side, from which the name of the city derives.
Within the castle, there are many facilities that can be visited such as: The National Historical Museum “Gjergj Kastrioti Skenderbeu”, the Ethnographic Museum, the Dollma Tekke, the Medieval Hammam, the Clock Tower, the Church of St. Ndreu, the Fatih Mosque, the Medieval Home and the Skenderbeg’s Olive Tree.