The Amberkhana, situated in the center of the fort, were three granaries built in the Bijapuri style of architecture. They enabled Shivaji to withstand a 5 month siege by Siddhi Johar. It consists of three buildings called the Ganga, Yamuna and Saraswati Kothis. The Ganga kothi, which was the largest, had a capacity of 25,000 khandis (with one khandi being 650 lbs). It covers an area of 950 sq m and is 10.5 m high. Rice, nachni and warai were the major provisions stored. Stairs on both sides lead the top of the buildings. It has sixteen bays each with its own flat vault with a hole on top through which grain used to be passed. The eastern entrance has a domed chamber with a balconey and plasterwork of the Bijapuri style.