The reach of Sher Shah's short reign is best measured in the systems he standardised. His personal rule lasted only about five years, from 1540 to 1545, yet the road he rebuilt โ the Sadak-e-Azam, later called the Grand Trunk Road โ ran for a couple of thousand miles across the Gangetic plain, in his time linking Sonargaon in Bengal towards the northwest, and in its fuller extent stretching from the eastern delta to the Khyber. Along it he planted rows of shade trees, wells and roughly some 1,700 sarais โ walled rest-houses that doubled as inns, relay-posts and the nodes of a dak, or postal, system where riders and horses were kept ready. His most enduring number is a weight: the silver rupiya he issued, around 178 grains (about 11.5 grams) of fixed purity, alongside a copper dam, which set the pattern for Indian coinage for centuries and gave the modern rupee its name. His land revenue reform rested on measurement โ surveying cultivated land, classifying it by fertility, and fixing the state's share, commonly around one-third of the produce, in cash or kind, recorded in written agreements with the cultivator. Exact figures vary between sources and should be read as orders of magnitude, but the direction is unmistakable: a state run by rule and record rather than guesswork.