Sion Hillock Fort

The Sion Hillock Fort went up between 1669 and 1677 under the English East India Company, while Gerard Aungier was Governor of Bombay, on top of a conical hillock 500 metres from Sion railway station. It marked the frontier between British-held Parel island and Portuguese Salsette across the creek to the north. It was notified as a Grade I heritage structure in 1925, and the Riwa and Sewri forts are nearby.

At the foot of the hill are the Archaeological Survey of India's Mumbai Circle office and the Pandit Jawaharlal Nehru Udyan garden. Paths climb to the fort, now a dilapidated jumble of broken steps, scattered walls and ruins overgrown with trees, with a small room on top of the wall. The view takes in the salt pans of the Thane Creek. Restoration began in 2009 but stopped partway for want of funds.