Qutub-Minar in red and buff standstone is the highest tower in India. It has a diameter of 14.32m at the base and about 2.75m on the top with a height of 72.5m.

Qutb-u'd-Din Aibak laid the foundation of Qutab Minar in AD 1199. The minar was said to have been built to celebrate the victory of Mohammed Ghori, the invader from Afghanistan, over the Rajputs in 1192. He raised the first storey, to which were added three more storeys by his successor and son-in-law, Shamsu'd-Din IItutmish (AD 1211-36). All the storeys are surrounded by a projected balcony encircling the Minar and supported by stone brackets, which are decorated with honeycomb design, more conspicuously in the first storey.

Numerous inscriptions in Arabic and Nagari characters in different places of the Minar reveal the history of Qutb. According to the inscriptions on its surface it was repaired by Firoz Shah Tughlaq (AD 1351-88) and Sikandar Lodi (AD 1489-1517).

Alau'd-Din Khalji commenced Ala'i Minar, which stands to the north of Kutub-Minar, with the intention of making it twice the size of Qutub Minar. He could complete only the first storey, which now has an extant height of 25 m. The other remains in the Qutab complex comprise Madrasa, graves, tombs, mosque and architectural members.