The Qutb Minar complex are monuments and buildings from the Delhi Sultanate at Mehrauli in Delhi, India. Construction of the Qutub Minar "victory tower" in the complex, named after the religious figure Sufi Saint Khwaja Qutbuddin Bakhtiar Kaki, was begun by Qutb-ud-din Aibak, who later became the first Sultan of Delhi of the Mamluk dynasty (Gulam Vansh). It was continued by his successor Iltutmish (a.k.a. Altamash), and finally completed much later by Firoz Shah Tughlaq, a Sultan of Delhi from the Tughlaq dynasty (1320–1412) in 1368 AD. The Qubbat-ul-Islam Mosque (Dome of Islam), later corrupted into Quwwat-ul Islam, stands next to the Qutb Minar.
Many subsequent rulers, including the Tughlaqs, Alauddin Khalji and the British added structures to the complex. Apart from the Qutb Minar and the Quwwat ul-Islam Mosque, other structures in the complex include the Alai Darwaza gate, the Alai Minar and the Iron pillar.
Inside the complex lie the tombs of Iltutmish, Alauddin Khalji and Imam Zamin.
Today, the adjoining area spread over with a host of old monuments, including Balban's tomb, has been developed by the Archaeological Survey of India (ASI) as the Mehrauli Archaeological Park, and INTACH has restored some 40 monuments in the Park. It is also the venue of the annual 'Qutub Festival', held in November–December, where artists, musicians and dancers perform over three days.
Alai Darwaza
left|thumb|Close up of the inscriptions on entrance arch, Alai Darwaza built by [[Alauddin Khalji]]
The Alai Darwaza is a main gateway from the southern side of the Qutub. It was built by the second Khalji, Sultan of Delhi, Ala-ud-din Khalji in 1311 AD, who also added a court to the pillared hall to the eastern side, it was to serve as one of four grand gates for his vast expansion to the Quwwat-ul-Islam mosque.. The domed gateway is decorated with red stone and inlaid white marble decorations, inscriptions in Naskh script, latticed stone screens, and showcases the remarkable craftsmanship of the Turkish artisans who worked on it. This is the first building in India to employ Islamic architecture principles in its construction and ornamentation. However, the unusually thick walls and shallow dome indicate that the builders had not yet mastered constructing domes. It has five distinct storeys, each marked by a projecting balcony carried on muqarnas corbel and tapers from a diameter 14.3 metres at the base to 2.7 metres at the top, which is 379 steps away. It is listed as a UNESCO World Heritage Site along with surrounding buildings and monuments.
Built as a Victory Tower, to celebrate the victory of Muhammad Ghori over the Rajput king, Prithviraj Chauhan, in 1192 AD, by his then viceroy, Qutb-ud-din Aibak, later the first Sultan of Mamluk dynasty. Its construction also marked the beginning of Muslim rule in India. It was built using red sandstone and marble. Inscriptions record that 27 Hindu and Jain temples were torn down and used for its creation. Even today the Qutb remains one of the most important "Towers of Victory" in the Islamic world. Aibak however, could only build the first storey, for this reason the lower storey is replete with eulogies to Muhammad Ghori. The next three floors were added by his son-in-law and successor, Iltutmish. The minar was first struck by lightning in 1368 AD, which knocked off its top storey, after that it was replaced by the existing two floors by Firoz Shah Tughlaq, a later Sultan of Delhi from 1351 to 1388, and faced with white marble and sandstone enhancing the distinctive variegated look of the minar, as seen in lower three storeys. Thus the structure displays a marked variation in architectural styles from Aibak to that of Tughlaq dynasty. The inside has intricate carvings of the verses from the Quran.
The minar made with numerous superimposed flanged and cylindrical shafts in the interior, and fluted columns on the exterior, which have a 40 cm thick veneer of red and buff coloured sandstone; all surrounded by bands of intricate carving in Kufic style of Islamic calligraphy, giving the minar the appearance of bundled reeds. It stands just outside the Quwwatul mosque, and an Arabic inscription suggests that it might have been built to serve as a place for the muezzin, to call the faithfuls for namaz. Also marking a progression in era, is the appearance of inscriptions in a bold and cursive Thuluth script of calligraphy on the Qutb Minar, distinguished by strokes that thicken on the top, as compared to Kufic in earlier part of the construction.
Inscriptions also indicate further repairs by Sultan Sikander Lodi in 1503, when it was struck by lightning once again. In 1802, the cupola on the top was thrown down and the whole pillar was damaged by an earthquake. It was repaired by Major R. Smith of the Royal Engineers who restored the Qutub Minar in 1823 replacing the cupola with a Bengali-style chhatri which was later removed by Governor General, Lord Hardinge in 1848, as it looked out of place, and now stands in the outer lawns of the complex, popularly known as Smith's Folly.
After an accident involving school children, entry to the Qutub Minar is closed to public since 1981, while Qutub archaeological area remains open for public. In 2004, Seismic monitors were installed on the minar, which revealed in 2005 Delhi earthquake, no damage or substantial record of shakes. The reason for this has been cited as the use of lime mortar and rubble masonry which absorbs the tremors; it is also built on rocky soil, which further protects it during earthquakes. It was built near the site of a pre-demolished large temple located in the centre of a citadel.