New York City moved closer to resuming its frenetic pace by getting back its vital subways today, three days after a superstorm left neighbouring New Jersey stunned by miles of coastal devastation.
Thousands of people in one city were still stranded by flood waters.
The decision to reopen undamaged parts of the United States' largest transit system came as the death toll reached more than 70 in the US and left more than five million without power. Hurricane Sandy earlier left another at least 69 people dead as it swept through the Caribbean.
In New York, people streamed into the city as service began to resume on commuter train and subway. The three major airports resumed at least limited service, and the New York Stock Exchange was open again.
Amtrak's Northeast Corridor - the busiest train line in the country - was to take commuters along the heavily populated East Coast again starting tomorrow.
But hundreds of thousands in New York City alone were still without power, especially in Lower Manhattan, which remained in the dark roughly south of the Empire State Building after floodwaters had knocked out power.
Concerns rose over the elderly and poor all but trapped on upper floors of housing complexes in the powerless area, who faced pitch-black hallways, lifts and dwindling food. New York's governor ordered food deliveries to help them.
In New Jersey, the once-pristine Atlantic coastline famous for the TV show Jersey Shore was shattered. President Barack Obama joined Governor Chris Christie in a helicopter tour of the devastation yesterday and told evacuees: "We are here for you. We are not going to tolerate red tape. We are not going to tolerate bureaucracy."
And warnings rose again about global warming and the prospect of more such severe weather to come.
"The next 50 to 100 years are going to be very different than what we've seen in the past 50 years," said S. Jeffress Williams, a scientist emeritus at the US Geological Survey's Woods Hole Science Centre in Massachusetts. The sea level is rising fast, and destructive storms are occurring more frequently, said Williams, who expects things to get even worse.
Across the Hudson River from New York City, the floodwaters remained in the city of Hoboken, where an estimated 20,000 people remained in their homes amid accusations that officials were slow to deliver food and water.
One man blew up an air mattress and floated to City Hall, demanding to know why supplies had not arrived.
The superstorm's effects, though much weakened, continued today. Snow drifts as high as five feet (1.5 metres) piled up in West Virginia, where the former hurricane merged with two winter weather systems as it went inland.
Across the region, people stricken by the storm were helping each other - providing comfort to those left homeless or offering hot showers and electrical outlets for charging mobile phones to those without power.
New York City Mayor Michael Bloomberg also ordered them to share cars. Television footage showed heavy traffic crawling into Manhattan as police turned away cars that carried fewer than three people - a rule meant to ease the congestion that paralysed the city earlier in the week.
After suffering the worst disaster in its 108-year-old history, the subways were to roll again - at least some of them. More than a dozen of the lines would offer some service, but none below Manhattan's 34th Street, a line of demarcation in the city separating the hardest-hit residents from those who escaped the brunt.
Central Manhattan, which includes the city's financial district, September 11 memorial and other tourist sites, was still mostly an urban landscape of shuttered shops and boarded-up restaurants, where people roamed in search of food, power and a hot shower.
Commuters lined up at Penn Station to board subway trains at 6 am.
But most of New Jersey's mass transit systems remained shut down, leaving hundreds of thousands of commuters stuck on clogged highways and in long lines at petrol stations. Atlantic City's casinos remained closed.
Not everyone was fazed by the superstorm and the chaos it caused. Yukun Yang, a college student, said his home city of Guangzhou, China, would have weathered the storm better than New York.
"We have hurricanes and subways in my city, and we handle it much better," he said. "Hurricanes are normal and they don't stop the subways."