Mumbai, or Bombay as many Indians still call it, is India's largest city, one of the world's greatest commercial centers and home to the vast, vibrant Bollywood film industry.
Some of the richest people on the planet live within its boundaries. But so does a multitude of poor. Half of Mumbai's population lives in slums.
The city, which overlooks the Arabian Sea, was built on a cluster of seven small islands, which were eventually united to become one big island. Every day hundreds of Indians arrive, drawn to the metropolis from the countryside in the hope of scratching out a living.
The property prices, which rival Manhattan or London, are well beyond the reach of most people, including the growing middle class.
The infrastructure is drastically overloaded. The roads are so crowded, despite a plethora of elevated highways built in recent years, that a journey of a few miles can take several hours. When the monsoon rains come, the place floods, walls collapse, electric wires short-circuit and roads turn into impassable rivers. In 2005, the monsoon-related death toll was more than 740 people
This all explains why an entire new city is being built on what were once mangrove swamps and fishing villages a few dozen miles along the coast to the east.
The city is called Navi — or new-- Mumbai. The project started back in 1970, on an area of 213 square miles, but for years it stagnated.
India's economic boom brought about a spurt of growth. Information technology, pharmaceutical, mobile phone and back office companies are among those that have moved in, and so has India's largest private sector company, Reliance Industries, led by the industrial magnate Mukesh Ambani. Reliance is investing vast sums in Navi Mumbai.
The population has grown to around two million, and it is adding around 100,000 people a year. It has new shopping malls, parks and wide uncrowded highways. The city has become a magnet for the young Indian professional: the average age is 28. City officials say the literacy rate is above 98 percent — way above the national average.
Opinions about Navi Mumbai are divided.
Leading Indian environmentalist Bhittu Sahgal calls it the "first step to hell." He points out that it is built at sea level, a mistake, he says, given the possibility of flooding due to climate change.
He says the livelihoods of fishermen were destroyed by the arrival of the new city, and so were swaths of mangrove swamps, an important habitat for fish and crabs.
One of those fishermen, R.B. Boya, testifies to the damage caused by urban growth. He is from the traditional Koli fishing community. They are the original inhabitants; they have worked the waters in and around Mumbai since well before the city existed.
Standing by his nets and his canoe, which is fashioned out of the wood of a mango tree, Boya explains that his catch has dropped off sharply in recent years. He blames the fact that the waters on which he relies are now badly polluted. Some days he catches nothing.
Kishore Rathod, news editor at the Navi Mumbai office of the daily newspaper DNA, has worked in Navi Mumbai for years, much of that time as a beat reporter. At first he thought the city would fail.
"There were no trees, there was no greenery. People used to say it's a malaria-infested place. It was a nightmare," he says.
He has changed his mind, and now sings the praises of his adopted home city.
Rathod says people are pouring in and earning good money — upwards of 30,000 rupees ($700) a month.
"Where will they spend that?" he says. "They need the malls. They need the food courts. They need the multiplexes. They need the theaters."
He says they also seem to need fancy cars: "You have the Hummers flying on the roads of Navi Mumbai. You have the Ferraris flying on the roads of Navi Mumbai. Now America is going to small cars, and we are talking about big cars."