Delhi officially National Capital Territory of Delhi (NCT), is the largest metropolis by area and the second-largest metropolis by population in India. Delhi is said to be one of the oldest existing cities in the world, along with Damascus and Varanasi. Legend estimates it to be over 5,000 years old.Delhi divided into two very different worlds, the 'old' and the 'new', each presenting deliciously different experiences. Spacious New Delhi was built as the imperial capital of India by the British; rambunctious Old Delhi served as the capital of Islamic India. Delhi is the home of three popular World Heritage Sites. They are Red Fort or Lal Quilla, Humayun's Tomb, and Qutub Minar.