<Tr> <Th> Constructed by </Th> <Td> Started construction by Qutub - ud - din Aibak & completed construction by Iltutmish </Td> </Tr> <P> The Qutub Minar (Hindi: कुतुब मिनार, Urdu: قطب مینار ‬ ‎) is a minaret that forms a part of the Qutab complex, a UNESCO World Heritage Site in the Mehrauli area of Delhi, India . Qutub Minar is a 73 - metre (239.5 feet) tall tapering tower of five storeys, with a 14.3 metres (47 feet) base diameter, reducing to 2.7 metres (9 feet) at the peak . It contains a spiral staircase of 379 steps . Its design is thought to have been based on the Minaret of Jam, in western Afghanistan . </P> <P> Qutab Ud - Din - Aibak, founder of the Delhi Sultanate, started construction of the Qutub Minar's first storey around 1192 . In 1220, Aibak's successor and son - in - law Iltutmish completed a further three storeys . In 1369, a lightning strike destroyed the top storey . Firoz Shah Tughlaq replaced the damaged storey, and added one more. Sher Shah suri also added an entrance to this tower while he was ruling and Humayun was at an exile . </P> <P> It derived its name from the Sufi saint Qutbuddin Bakhtiar Kaki whom Qutab Ud - Din - Aibak revered . The Minar is surrounded by several historically significant monuments of the Qutab complex, including Quwwat - ul - Islam Mosque, which was built at the same time as the Minar, and the much older Iron Pillar of Delhi . The nearby pillared Cupola known as "Smith's Folly" is a remnant of the tower's 19th century restoration, which included an ill - advised attempt to add a sixth storey . </P>

Who started and completed the construction of qutub minar
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