Kolaba Fort is situated in the sea at a distance of 1-2 km from the shores of Alibag in the Konkan region of Maharashtra, India and is an old defensive structure consisting of walls or mounds built around a stronghold to strengthen it. It was built in 1652 by Chatrapati Shivaji Maharaj to keep a check on the actions of the foreign naval powers of English, Portuguese and the Siddhi of Janjira. The fort has 25 feet high walls with two main doors, one on the sea side and the other heading towards Alibag. In the monsoon time, one can reach the fort by walking through waist-deep water at low tide and boats must be used at the time of high tides. Even though the fort is on seaside, one gets amazed to see freshwater wells inside the fort.