While tourists are visiting the Qutab Minar during their holiday in Delhi, their guide will probably show them other nearby attractions like the iron pillar. It is recognised all over the world as a proof of the skill of Indian blacksmiths as for more than 900 years, it has not corroded. This property is credited to the use of iron, rich in phosphorus by the blacksmiths to cast the tower. Its total height is around 7.21 metres and a part of it, measuring further 1.21 metres in length is below the ground. The pedestal on its top is about 1.07 metres high and its bulbous base rise to roughly 0.74 metres. The frame, beneath the stone-path, on which it stands, is made of iron bars, soldered together with lead. Its diameter reduces from about 420 mm at its base to around 306 mm at its top due to its conical structure.
A commonly accepted theory is that the pillar was not forged in the city, but brought from somewhere else. Some historians say that it originally stood inside the Udayagiri Caves in Madhya Pradesh. This theory is supported by the proven facts that speak of peculiar mining traditions around the Deccan Plateau in Central India. Furthermore, it is hypothesised that Iltutmish, the third Mamluk ruler and the first Sultan of Delhi, sacked the above-mentioned region and brought the pillar to Delhi. Its surface contains many inscriptions, carved in different time periods, but never studied properly. An inscription here, in the Sanskrit language, is thought to be the earliest such carving. As it is written in the Brahmi script, it is held that it was perhaps forged during the reign of the Gupta dynasty.
This inscription says that it was erected to honour Lord Vishnu and also praises a king named Chandra. Some historians identify this king with Chandragupta of the Gupta dynasty and others link him with Chandragupta Maurya. If it was indeed erected during the time of Chandragupta Maurya, the tower today, is more than 1300 years old. Some people also say that it was constructed as early as 9th century BC, but this theory has largely been cast aside. As Qutab Minar is among the most prominent tourist attractions of India, almost all inclusive holiday packages in India include it in their itinerary.