Mughal fort in Old Delhi, India. It was so called because of its red sandstone walls, which enclosed palaces, gardens, barracks, and other buildings. It was built by Shāh Jahān in the mid-17th century and remains a main tourist attraction. The fort's complex was designated a UNESCO World Heritage site in 2007.

An earlier Red Fort had been built in Old Delhi in the 11th century by the Tomara king Anangapala. The Quṭb Mosque now stands on the site.