Tughlaqabad Fort is one of the largest and most impressive medieval forts in India. It was built in 1321–1325 CE by Ghiyas-ud-Din Tughlaq, the founder of the Tughlaq dynasty, as the capital of the Delhi Sultanate. Spread across nearly 6.5 square kilometers, the fort is surrounded by massive stone walls, bastions, watchtowers, gateways, and the remains of royal palaces, audience halls, mosques, and underground passages. Although now in ruins, it remains an outstanding example of medieval military architecture and offers panoramic views of Delhi. The nearby Tomb of Ghiyas-ud-Din Tughlaq, connected by a historic causeway, is another major attraction.