Although archeologist claim that the settlement around Delhi dates back far beyond the days of Christ but it was only during the Medieval era that Delhi begins to take on shades of a city.
Over the centuries Delhi several rulers have developed their very own citadel in different parts of Delhi, which together give rise to the modern day city of Delhi, or rather New Delhi. Seven such citadels can be traced. The seven cities of Delhi are:
First City: Lal Kot (Qila Rai Pithora) by Prithviraj Chauhan.
Second City: Siri by Alauddin Khalji.
Third City: Tughluqabad by Ghiyasuddin Tughluq.
Fourth City: Jahanpanah by Muhammad bin Tughluq.
Fifth City: Firozabad by Firoz Shah Tughluq.
Sixth City: Dinpanah / Purana Qila by Sher Shah / Humayun.
Seventh City: Shahjahanabad by Shah Jahan.
Delhi remained the axis of Mughal empire until the revolt of 1857 and became the capital of British India in 1911. Today it is the capital of modern India and is an interesting mix of old & new architecture.