Dehradun , also rendered Dera Doon, is the winter capital and most populous city in the Indian state of Uttarakhand. It is the administrative headquarters of the eponymous district. Part of the Garhwal region, it lies along National Highway 7 with the distance of 236 kilometres (147 mi) north of India’s capital New Delhi and is served by Dehradun railway station and Jolly Grant Airport.