In November, I took the train to New York City for the fall meeting of the Urban Land Institute, while I was there I stayed at the New York Hilton & Towers on the Avenue of the Americas.

The trip from start to finish lasted about 26 hours -- enough time to develop some lasting impressions.

Let me begin by saying that it's much easier to get from place to place in the Northeast Corridor; the NE Corridor is a stretch of railroad linking Washington to Boston.

That's especially true from Philadelphia, where I boarded the train to Manhattan. The trip took about an hour and five minutes -- about 15 minutes less than my last trip to New York six months before.

Amtrak is expensive -- an $88 roundtrip with my AAA discount -- but when you calculate driving time, wear and tear on the car, and overnight parking costs in Manhattan, you probably save a little.

I also enjoyed the New York City subway system as it's very easy to use. I mean, for two dollars a trip, you can go safely, quickly, and to almost any location when you want to.

The neighborhood around the hotel had improved since I had last stayed at that hotel 25 years before. In 1979, New York seemed dangerous and in decline. I was attending a meeting of the American Historical Association at the hotel, and I never ventured outside during my four-day stay.

I probably had imagined a lot of it, but the opinion seemed to be shared by even the New Yorkers attending. Since I was urban pioneering it in Hartford, Conn., back then, I considered myself very street-smart.

This time it was election night, and after a dinner several blocks from the hotel, I started walking back. It was 11 p.m. The hotel was a ten minute walk at most, but, since I spent the next two hours exploring the neighborhood, it took me much longer to get there.

The difference between then and now: People. People in their apartments and condos, people on the street, people in restaurants and bars, vendors in their carts, newspaper sellers, police officers. People, people, people.

It's like that in a lot of cities these days: Downtown Philadelphia, Chicago, San Francisco, Toronto, Boston, just to name a few.

America has rediscovered its cities. But, as ULI president Richard M. Rosan told a recent meeting in Cannes, France, building competitive cities means building more than just places to live and work.

"It's about creating places that inspire, places with character, places that draw people through a powerful sense of identity," he said.

Rosan points out that in many cities, the economy is increasingly driven by creative, "knowledge" workers who tend to be well educated, financially comfortable, and highly mobile.

While city cores once relied heavily on manufacturing and industries as their economic engines, "they now rely on these new residents -- young, childless professionals, older workers and retirees -- for both economic and social stability," Rosan said.

"We are seeing a broad push worldwide by cities, to reinvent themselves to accommodate the knowledge-based, globalized economy," he said.

The most successful urban regeneration efforts are based on:

Strong political leadership. Rosan believes that every thriving city is run by creative, progressive leaders who are willing to challenge the conventional ways of doing things, to experiment, and be open to new ideas.

An environment for intellectual stimulation and creativity -- a "brain-gain" city rather than a "brain-drain" city. This means offering a vast array of arts, entertainment, recreation and culture.

An environment that is tolerant of diversity. Talented people come in all genders, ethnic groups, and income brackets, Rosan said.

A commitment to provide housing to people with a variety of incomes. Having an adequate supply of affordable housing is critical for cities to thrive.

A solid track record in creating long-lasting, public-private partnerships.

A commitment to a transit-oriented development and transportation infrastructure.

A willingness to aggressively preserve land for parks and open space. The most successful cities are those that place a high value on the public realm -- the places that are open and accessible to all; the inclusive places where people gather and create memories.

"These factors will have a long-term impact on the way our cities are developed and redeveloped, and on the way our cities are perceived and marketed around the world," Rosan said. "Our cities are being rediscovered, not just as places to visit, but as energetic, wonderfully diverse places to live."

The cities that are able to offer a high quality of life in the forms of efficient transportation, recreational and cultural amenities, diverse neighborhoods and a safe, clean, lively environment "will be the winners," Rosan said.