Explanation:

Asirgarh Fort is an Indian fortress (qila) situated in the Satpura Range about 20 kilometres (12 mi) north of the city of Burhanpur, in the Indian state of Madhya Pradesh. Because the fortress commands a pass through the Satpuras connecting the valleys of the Narmada and Tapti rivers, one of the most important routes from northern India to the Deccan, it was known as the "key to the Deccan". During the Mughal Era, it was considered that the Deccan started here while the empire from Asirgarh to Delhi was considered Hindustan.