The Arnala Fort is located on an Island and is at a distance of 8 miles north of Vasai, In Maharashtra. Since this is an Island fort, this is also known as Jaldurg or Janjire-Arnala. The Island fort was initially built by the Portuguese, who also owned this fort and later rebuilt and named it Ilha das vacas.
Octagonal Water Reservoir and Temples: Inside the Island fort there is huge octagonal fresh water reservoir , along with temples which are dedicated to various gods and goddesses, like Lord Shiva, Ambakeshwar, Goddess Bhavani, , and one can also see the tombs of Hajjali and Shahali. The sacred sandals or 'paduka' belonging to Shrinityanand Maharaj have also been preserved here in a dome on the eastern face of the fort.
The main entrance of the fort is in the Northern direction. There is a solid stone doorway which is beautified with pictures of tigers and elephants. In the Southern end of the island there is a Southern Watch Tower, this is located at a distance of 550 meters from the main fort. There are no entrance gates for this tower.