 Babur used the city as a base for expeditions to other nearby towns in Pashtunistan.Under the reign of Babur's son, Humayun, direct Mughal rule over the city was briefly challenged with the rise of the Pashtun king, Sher Shah Suri, who began construction of the famous Grand Trunk Road in the 16th century.Peshawar was an important trading centre on Sher Shah Suri's Grand Trunk Road.