The Qutub Minar, also spelled as Qutab Minar, or Qutb Minar, is the second tallest minaret in the world made up of bricks. The minaret 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 top of 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.