The Grand Trunk Road is among the oldest trade routes in the Indian subcontinent. Though ancient in origin, it was significantly improved by Sher Shah Suri, who built sarais, milestones and planted trees along its sides. The road connects Kolkata (formerly Calcutta) in eastern India to Amritsar in northern India, continuing further into Pakistan and Afghanistan. Historically, it served as a major communication and trade artery for merchants, travelers, soldiers and administrators. Its strategic importance helped unify diverse regions and facilitated the movement of goods, ideas and culture. Throughout Mughal and British periods, the GT Road remained central to governance and trade.