The Qutb Minar Rises 72.5 Metres in Five Storeys, the Tallest Masonry Tower in India, and Has Been on UNESCO's World Heritage List Since 1993 With a Gupta-Era Iron Pillar in Its Courtyard

UNESCO put the Qutb Minar and its Monuments, in Mehrauli on the southern edge of Delhi, on the World Heritage List in 1993 under a single criterion, (iv). Its text measures the red and buff sandstone tower at 72.5 metres and calls it the tallest masonry tower in India. The Archaeological Survey of India (ASI), which owns and manages the complex, says Qutb ud-Din Aibak laid the foundation in AD 1199.

What UNESCO inscribed

UNESCO’s wording for criterion (iv) at this site is that the religious and funerary buildings of the complex are “an outstanding example of the architectural and artistic achievements of early Islamic India”. The ICOMOS evaluation of October 1993, the advisory body’s report that recommended inscription, recommended the same criterion and the same wording.

UNESCO’s statement describes the whole ensemble as a testimony to what the Islamic rulers built after they first established their power in the subcontinent in the 12th century. It lists the Qutb and Alai minars, the Quwwat-ul-Islam mosque and its extension, a madrasa of Alauddin Khalji, the tomb of Iltutmish, the Alai Darwaza gateway and the Iron Pillar inside one boundary. It also says the property is owned by the Government of India and managed by the ASI.

Five storeys, and dates that do not agree

The ASI’s account is that Aibak laid the foundation in 1199 and raised the first storey, and that his son-in-law and successor Iltutmish (1211 to 1236) added three more. That makes four. The 1993 ICOMOS evaluation, hosted by UNESCO, says the present tower has five, because the topmost of the original four was replaced by two in Firuz Shah Tughlaq’s reign. The tower is 14.32 metres across at the base and 2.75 metres at the top. Its three lower storeys are fluted differently: alternating angular and rounded flutes at the bottom, rounded in the middle and angular above, with balconies carried on honeycomb-patterned brackets between them.

The sources give different start dates. The ASI says 1199. The ICOMOS evaluation says Aibak began it around 1202, and UNESCO’s page on the Minaret of Jam says the Minar was begun in 1202 and finished in the early 14th century. UNESCO’s own statement for the Qutb complex has Aibak and Iltutmish building it between 1199 and 1503, a span that runs to Sikandar Lodi’s restoration. Aibak lived from 1150 to 1210, according to Britannica, which says the tower still stands to commemorate his victories.

Repairs are well recorded. The ASI says inscriptions on the shaft show Firuz Shah Tughlaq (1351 to 1388) and Sikandar Lodi (1489 to 1517) repaired it, and that Major R. Smith restored it in 1829. ICOMOS adds that lightning damaged it in 1326 and 1368, that work followed an earthquake in 1803, and that the original cupola fell in a quake. A replacement in late Mughal style was taken down in 1848 and now stands on the lawns south-east of the tower. Structural work followed in 1920, 1944 to 1949, 1971 to 1972 and 1989 to 1992.

A victory tower with a Ghurid model

The tower’s purpose has more than one reading. The ASI says Aibak founded it for the muezzin’s call to prayer. ICOMOS notes that a later Nagari inscription calls it Alauddin’s “victory monument”, Vijaya-stambha in Sanskrit. UNESCO’s text says the builders drew on references from their Ghurid homeland, and its page on the Minaret of Jam, a 65 metre brick tower built in 1194 in what is now Afghanistan, names the Qutb Minar as an example of that tradition reaching India. Daniel Waugh of the University of Washington suggests the Qutb Minar was more a symbol than a place for the call to prayer.

The mosque built beside it

The Quwwat-ul-Islam mosque, whose name UNESCO translates as the Might of Islam, is the oldest surviving mosque built by the Delhi Sultans, according to the ASI. It has a rectangular courtyard enclosed by cloisters of carved pillars and an arched screen on the west. UNESCO’s text says it introduced to India the classic model of Islamic architecture that had developed in western Asia, and that its pillars and cladding incorporate temple elements.

The ASI gives 1198 for its construction by Aibak, and ICOMOS says work ran from 1192 to 1198. Waugh puts completion in 1197. The ASI says the cloisters were built from the columns and members of 27 Hindu and Jaina temples, as Aibak’s own inscription on the main eastern entrance records. UNESCO’s short description says some 20 Brahman temples. The ASI says a lofty arched screen was added later and that Iltutmish and Alauddin Khalji enlarged the mosque, while ICOMOS places the high screen in the 14th century. The ground was already a fortress: the ICOMOS history says Lalkot, the first of Delhi’s seven cities, was founded by the Tomar ruler Anang Pal. Britannica says Muizz al-Din Muhammad of Ghur had conquered Delhi by 1193 and left Aibak in charge there, and the battles of Tarain article covers the fighting that came first.

The pillar in the courtyard

The Iron Pillar stands in the mosque courtyard. The ASI says its Sanskrit inscription, in fourth-century Brahmi script, records that it was set up as a standard of Vishnu on a hill called Vishnupada in memory of a king named Chandra, and a socket on the capital suggests an image of Garuda once stood on it. ICOMOS gives its length as 7.02 metres, 0.93 of it below ground, and calls it the largest known composite iron object from so early a period, built from hundreds of small wrought-iron blooms welded together. The metallurgist R. Balasubramaniam of IIT Kanpur puts its weight at nearly 6,000 kilograms.

Dates vary here too. ICOMOS says Chandra is believed to be the Gupta king Chandragupta II (375 to 413). Balasubramaniam dates the script to between 400 and 450 and places construction in the first quarter of the fifth century. A 2021 paper in Scientific Reports says about the fifth century. For the Gupta background see the Gupta golden age, and for the metallurgy see the full article on the pillar.

On corrosion, Balasubramaniam’s 2000 paper in Corrosion Science analysed rust from the pillar and reported crystalline iron hydrogen phosphate hydrate next to the metal as the critical factor in its resistance, formed with the help of the iron’s phosphorus, which he cites as about 0.25 per cent on average, and Delhi’s alternating wet and dry spells. The 1993 ICOMOS text had listed wrought iron, Delhi’s climate and probable anointing with ghee. The Scientific Reports authors, who studied iron made by Agaria smelters in central India and could not sample the pillar because it is a protected monument, write that several theories have been postulated for it. Balasubramaniam’s paper also reports that the buried part of the pillar has corroded more than the exposed part, which he attributes to galvanic action with the lead coating applied when it was re-erected in the 19th century.

Tomb, gateway and an unfinished minar

UNESCO says Iltutmish’s square tomb, built in 1235 in the north-west of the mosque, marks the beginning of the tradition of royal tombs that continued into the Mughal era. His daughter is the subject of the Razia Sultan article. Alauddin Khalji’s additions between 1296 and 1311 include the Alai Darwaza, the southern gateway of the mosque enclosure. An inscription dates it to AH 710, or AD 1311, and the ASI calls it the first building in the complex to use Islamic principles of construction and ornamentation. Waugh calls its arches among the earliest using Islamic world techniques, and says its dome shows local builders had not yet mastered advanced dome construction. UNESCO’s short description calls the gate a masterpiece of Indo-Muslim art.

Alauddin also began the Alai Minar, planned at twice the scale of the Qutb Minar. UNESCO and the ASI give its first storey as 25 metres high today, while the 1993 ICOMOS report says he died before it reached the first storey and work stopped. Delhi at a glance places the complex among the capital’s three World Heritage Sites.

Visiting, and the ASI’s rules

The ASI page says the complex is open from sunrise to 8 pm, while Incredible India says sunrise to sunset, which may vary by season. Children below 15 enter free. The ASI lists Rs 50 cash or Rs 35 online for visitors from the SAARC and BIMSTEC countries, and Delhi Tourism’s copy of the notice names Indian citizens in that group. Other foreign visitors pay Rs 600 cash or Rs 550 online. Fees can be revised, so the ASI’s current notice is the one to check before a visit.

The Ancient Monuments Rules of 1959, hosted by the ASI, bar damaging any part of a protected monument, firing a gun, and cooking or eating except where permitted. They also bar selling goods, guiding or taking photographs for money without a licence from an archaeological officer, begging, and bringing animals or vehicles beyond parking areas.

The ASI page lists no climb of the Minar. On 4 December 1981 a power failure plunged its staircase into darkness, and United Press International reported 45 dead, 23 of them children according to police. Gulf News also gives 45, counts 20 schoolchildren among them and reports that visitors have been barred from the staircase since.

In financial year 2024-25 the Ministry of Tourism’s compendium, using ASI data, lists 3,204,760 domestic and 220,044 foreign visitors to the Qutub Minar, the third-highest figure in both lists of ticketed ASI monuments.