As Delhi prepares for the Commonwealth Games in 2010, former BBC South Asia correspondent Sam Miller finds how the ancient city is changing at breathtaking speed.
Delhi has a population of more than 15 million
The inhabitants of India's other great cities, Mumbai (Bombay) and Calcutta, used to sneer at Delhi with its much smaller population, and its supposed lack of sophistication.
"It's a collection of villages," they would say. "A fossil, a reminder of past empires. Not a real city."
They would joke: "Delhi has got no culture
just agriculture." They would say it was boring and sleepy.
But Delhi has begun to emerge from the shadow of Mumbai and Calcutta, and even provokes a certain amount of jealousy.
It is now - depending on how you calculate such things - one of the five most populous cities in the world, with a cultural life that equals or surpasses that of its Indian rivals.
Delhi attracts migrants from all over India (as well as some like me, from the rest of world) and is now the most cosmopolitan and fastest-growing of India's large cities.
It has one of the world's best metro railway systems, with more than 50 stations being added to the network over the next 15 months.
It is also visibly preparing for its next moment of anxiously anticipated glory, the Commonwealth Games of 2010.
Unsurprisingly, then, there are construction sites all over the city. But despite this extraordinary speed of development, Delhi remains both the leafiest and most archaeologically impressive of the world's megacities.
Most evenings, just before sunset, I walk or run in a huge secret park in the heart of modern Delhi.
It is really a jungle with footpaths, known only to those who live close by.
And peeking out of the jungle are the ruins of one of Delhi's earlier incarnations, known as Siri Fort, the capital of the Khilji dynasty built in the early 14th Century.
These ruins include one magnificent cathedral-like building - three stories high - that always seems destined to topple over in the next storm. It is popular with peacocks, but I have never seen another human there.
Delhi is littered with such ancient ruins, so many indeed that the ones in my park are not even included by the Archaeological Survey of India in a list of more than 1,000 heritage buildings in the city.
Anywhere else in the world these ruins would be a major tourist attraction.
Parts of the walls of Siri were recently excavated and restored and the workmen told me why they were doing it.
"It's for the Commonwealth Games," they said.
Except of course it is not. These ancient walls have absolutely nothing to do with the Games, which have become kind of Delhi shorthand for any piece of urban development that the authorities want to be completed by 2010.
Two summers ago, back in my local jungle park, I found another ruin, in an area of wilderness so thick with undergrowth that I had to beat my way through it with a stick.
Despite its age the mosque failed to capture public interest
There, long-forgotten, was half a mosque, a tree growing out of one of its walls, but the perfect rosettes and squinches created by artisans 700 years ago still intact.
I tried to interest my friends and fellow journalists in my discovery of an unlisted ancient mosque in the heart of modern Delhi.
I told people about it at Delhi parties and they yawned. I telephoned a leading historian of the medieval Sultanate period, who promised he would get back to me.
A guide book writer did come to see and she told me it will be mentioned in the next edition. But I failed to get anyone else half as excited as me.
I tried the internet, joining a "treasure hunt" website called geocaching.com
I hid my treasure - a few coloured paper clips in a plastic jar - inside the mosque, and posted the map co-ordinates on the website. I waited for eager treasure hunters to track down the mosque.
I went away on holiday and an irate American traveller posted a note on the website to say the co-ordinates were wrong and that he had been chased away by an angry pig.
In a city boasting such archaeological riches, smaller ruins may go unnoticed
On my return I went back to the mosque and discovered that my co-ordinates were correct. The American had not gone to the wrong place. The mosque had gone.
It had been bulldozed and there was no sign it had ever existed.
The wilderness had become a building site and squash and badminton courts were being built for - yes - the Commonwealth Games.
No-one made a fuss and I have found it hard to make the case that this archaeologically super-rich city is much poorer without one old tumbledown mosque.
And though I have been able to immortalise it in photos and text in a book I wrote about my adoptive city, I am also aware that it is just one of dozens of minor ruins that have disappeared in recent years.
And more will almost certainly go as the pace of development continues to accelerate.
Delhi is a city that is more proud of its future than its past.
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