Although Skopje is built on the foot of Mount Vodno, the urban area is mostly flat. It comprises several minor hills, generally covered with woods and parks, such as Gazi Baba hill (325 m), Zajčev Rid (327 m), the foothills of Mount Vodno (the smallest are between 350 and 400 m high) and the promontory on which Skopje Fortress is built.