This is the largest and the best-preserved Portuguese bastion in Goa and was built in 1609-12, to control the entry into the river Mandovi and to protect Old Goa from potential enemy attacks. A freshwater spring - from where the fort derives it's name - within the fort provided water supply to the ships that called there. Ringed by thick battlements, the heart of the fort was protected by two hundred cannons and a deep dry moat, which one still has to cross to get inside. Strategically located at the estuary of the river Mandovi, this fort was constructed in 1612 as a guard against invasions from the Dutch and the Marathas. The walls of this fort are 5 metres high and 1.3 metres wide. Little surprise then that this remains to be the only fort that was not conquered by any invaders during the 450 yearlong rule of the Portuguese empire. The area around the fort housed a large well and a number of springs that provided fresh drinking water to the voyagers that arrived by ship. ...