or Rewa Fort at Dharavi was constructed by the Portuguese during the early 17th century and remained under their control until 1665 when the British gained control over it. Because it was made using black stone, the locals commonly refer to Riwa Fort as the Kala Killa (Black Fort). In 1739, the island of Salsette was ceded to the Marathas and their power became obvious to everyone, including the British. They realized the importance of the Riwa Fort in helping them beat the Marathas and began to use it as a watchtower. It is located next to the Dharavi Bus Depot.