The underwater explorations on the western side of the Vijaydurg Fort, about 100 m seaward revealed a stone structure at a water depth of 8 to 10 m It measures 122 m in length, 7 m in width and 3 m in height. Besides it a tidal dockyard was also located around 3 km from Vijaydurg fort on the left bank of Vaghotan river. The dockyard is 110 m and width is 75 m. It was hollowed out of a rock. The southern and eastern side is cut out of a natural rock and rest is dry masonry. In addition to this a number of grapnel and triangular stone anchors were noticed in the adjoining area of dockyard.
Sindhudurg, the Ocean Fort was constructed by the Maratha King Shivaji
on a low island about 1 kilometer off Malwan. Probably Malwan was a
port in ancient times. During Satavahana rule in this region the ports
of Maharashtra were reached to their zenith. In cosurse of exploration
three 
triangular and three grapnel types of stone anchors were noticed at the entrance of the Sindhudurg fort. Anchors were made out of local available sand stones. Presently these anchors are cemented on the platform of the small jetty of the fort, presently, two other grapnel type of stone anchors are used as the mooring stones. The original place of these anchors is not known. But, it should be from nearby area only, where there might have been a number of ancient wrecks. The submerged rocks of adjoining area caused for wrecks due to inexperienced navigation. Local fishermen informed about the several shipwrecks behind the fort.
