Vijaydurg (sometimes written as Viziadurg), the oldest fort on the Sindhudurg coast, was constructed during the regime of Raja Bhoja II of the Shilahar dynasty (construction period 1193-1205) and restructured by Shivaji Maharaj. Earlier, the fort encompassed an area of 5 acres (1 acre = 4840 square yards or 4047 square metres) and was surrounded by sea on all four sides. Over the years the eastern trench was reclaimed and a road constructed thereon. Presently the area of fort is about 17 acres and is surrounded by the Arabian Sea on three sides.
Shivaji extended the area of the fort by constructing three walls on the eastern side, each 36 metres high. He also constructed 20 bastions. According to legend, this is one of only two Maratha forts where Shivaji personally hoisted the saffron flag. The other fort is Torna. Vijaydurg Fort was called the "Eastern Gibraltar", as it was virtually impregnable. Its locational advantages include the 40 km long Waghotan/Kharepatan creek. Large vessels cannot enter the shallow water of this creek. Also, Maratha warships could be anchored in this creek and yet remain invisible from the sea. It is a protected monument.