Delhi's centers of gravity have kept right on shifting. As it expanded through the 20th century, the city was organized into self-contained vihars or "colonies" (Lodi Colony, Jor Bagh, Vasant Vihar, and so on), each with its own market, school, and services -- and its own distinct character. Moving across the city, you get a sense that it is not just seven but a hundred discrete villages.

You also realize how shockingly green Delhi is. Riding in a taxi that first visit, mere blocks from Parliament, I stared dumbfounded as we passed a dense and seemingly endless forest. I asked the driver what it was, and he waved his hand dismissively: "That? That's just jungle." Jungle, in a city of 17 million! (It was actually the Central Ridge, a 2,134-acre reserve populated with jackals and wild boar.)

Whole swaths of the city are still given over to gardens, parks, and protected woodlands. In New Delhi, each major thoroughfare is lined with a particular species of tree -- neems on Janpath, tamarinds on Akbar Road, banyans on Willingdon Crescent. Then there's Lodi Garden, one of the world's great urban parks. I suppose New York could compete if Central Park had 14th-century tombs of Afghan emperors or thousands of emerald-colored parakeets. Lodi's treetops are aflutter with birds: black drongos, Indian tree pies, mynahs, red-vented bulbuls. But the park is also a functional playground: joggers in tracksuits rest on crumbling mausoleum stairs; yogis do sun salutations beside the pond; vendors proffer glasses of cool jal jeera -- salty limeade with cumin and mint -- while picnicking families keep an eye on greedy macaques. (Wild monkeys are a growing nuisance in Delhi's parks; the city has hired a corps of a hundred monkey-catchers to solve the problem.)

Photograph: Prakash Singh/AFP/Getty Images