Tughlaqabad Fort is a ruined fort and city in Delhi built by Ghiyas-ud-din Tughlaq.

Tughlaqabad fort, situated as it was on high rocky ground, was ideally located to withstand sieges. Ghiyas-ud-din Tughlaq helped matters along by putting up formidable walls which, though short on aesthetic value, are excellent examples of solid unimaginative masonry and not the type that any invading army could hope to scale in a hurry. Tughlaq put ramparts towering at heights of anywhere between 9m (30ft) to 15.2m (50ft), and rising up to 29.8m (98ft) around the citadel, between himself and the Mongols.