Listed as UNESCO World Heritage Site, the Qutb Minar and its monuments are an important example of Indo-Islamic Architecture. Qutub Minar is the tallest brick minaret in the world and stands in the Qutab Complex located at Aurabindo Marg, near Mehrauli, 14 Km south of Connaught place in Delhi. The complex has a number of other important monuments- the gateway built in 1310, the Alai Darwaza, Quwwat-ul-Islam Mosque; one of the oldest existing mosques in India, the tombs of Altamish, Alauddin Khalji and Imam Zamin; the 2000 year old 7m high Iron Pillar- the Alai Minar; another tower 27m high, the Madrasa or School, great screen of Qutbuddin Aibak in the mosque etc.

The Qutub Minar is 72.5 metres high (237.8 ft) and requires 399 steps to get to the top, although it has not been possible for visitors to ascend the tower for some years, due to safety reasons. The diameter of the base is 14.3 metres wide while the top floor measures 3.8 metres in diameter.

Qutb-ud-din Aybak, the first Muslim ruler of Delhi, commenced construction of the Qutub Minar in 1193; but could only complete its basement. His successor, Iltutmish, added three more storeys and, in 1368, Firuz Shah Tughluq constructed the fifth and the last storey. The development of architectural styles from Aybak to Tughluq are quite evident in the minaret. Like earlier towers erected by the Ghaznavids and Ghurids in today's Afghanistan, the Qutub Minar comprises several superposed flanged and cylindrical shafts, separated by balconies carried on Muqarnas corbels. The minaret is made of fluted red sandstone covered with intricate carvings and verses from the Qur'an, and is built on the ruins of Lal Kot, the Red Citadel in the city of Dhillika. The minar was said to have been built to celebrate the victory of Mohammed Ghori, the invader from Afghanistan, over the Rajputs in 1192 and Qutb-ud-din Aybak was inspired with the Minaret of Jam in Afghanistan and wanted to surpass it in all aspects.

Qutub Minar, as seen from a surrounding gate, and its height in comparison to humans.The purpose for building this beautiful monument has been speculated upon, apart from the usual role of a minaret—that of calling people for prayer in a mosque—in this case the Quwwat-ul-Islam mosque to the northeast of minar in AD 1198. It is the earliest extant mosque built by the Delhi Sultans. Many historians believe that the Qutb Minar was named after the first Turkish sultan, Qutb-ud-din Aibak but others contend that it was named in honour of Khwaja Qutb-ud-din Bakhtiar Kaki of Ush, a saint from Baghdad who came to live in India who was greatly venerated by Iltutmish. According to the inscriptions on its surface it was repaired by Firuz Shah Tughlaq (AD 1351–88) and Sikandar Lodi (AD 1489–1517). Major R.Smith also repaired and restored the minar in 1829.

All the storeys of Qutub Minar 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. Quwwat-ul-Islam Mosque, to the northeast of Minar was built by Qutbu'd-Din Aibak in AD 1198. It is the earliest mosque built by the Delhi Sultans. It consists of a rectangular courtyard enclosed by cloisters, erected with the carved columns and architectural members of 27 Hindu and Jain temples, which were demolished by Qutbu'd-Din Aibak as recorded in his inscription on the main eastern entrance.

The Iron Pillar in the courtyard bears an inscription in Sanskrit in Brahmi script of 4th century AD, according to which the pillar was set up as a Vishnudhvaja (standard of Lord Vishnu) on the hill known as Vishnupada in memory of a mighty king named Chandra. A deep socket on the top of the ornate capital indicates that probably an image of Garuda was fixed into it.

The Tomb of IItutmish (AD 1211-36) was built in AD 1235. It is a plain square chamber of red sandstone, profusely carved with inscriptions, geometrical and arabesque patterns in Saracenic tradition on the entrances and the whole of interior. Some of the motifs viz., the wheel, tassel, etc., are reminiscent of Hindu designs. Ala 'i- Darwaza, the southern gateway of the Quwwat-ul-Islam mosque was constructed by Alau'd-Din Khalji in AH 710 (AD 1311) as recorded in the inscriptions engraved on it. This is the first building employing Islamic principles of construction and ornamentation.

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 earlier 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.