Qutab Minar

Once the tallest monument in the world, now a World Heritage Site
Noteworthy for: This is India's most visited monument, attracting around 3.9 million visitors every year - more than the Taj Mahal.

Word to the wise: While entry into the tower itself is no longer permitted, for INR 10 per five minutes you can view the scenery via a little webcam on top.
A witness to the glorious and often bloody history of Delhi, the Qutab Minar was built by Qutub-ud-din Aibak (the first Muslim King of India) to mark his victory over the Hindu King Prithviraj Chauhan.

Just over 70 metres tall, its construction was completed in 1235. The minaret, part of the larger Qutab Complex, has five storeys separated by balconies, each with a different design. At the base of the minaret lies the first mosque built in India.

Nearby is an iron pillar which dates back to the 4th century BC. Legend has it that the person who can encircle the entire pillar with his arms, with his back towards it, will have their wish granted. There has now been a fence erected to protect the pillar from the corrosive effects of sweaty contestants.