Taking a stroll around Center City today can go a long way toward understanding why City Council, the Pennsylvania legislature, and politicians of every stripe support the $700 million expansion of the Convention Center.

Its opening almost 15 years ago was a key component of the transformation of Center City from a place where retailers shuttered their shops at dark to the lively urban core it is now.

Paul Levy, president of the Center City District business-improvement organization, cites the center, along with revival of South Broad Street as the Avenue of the Arts; conversion of a dozen older buildings into hotels and construction of new ones; opening of the National Constitution Center, the Independence Visitors Center, the Liberty Bell pavilion, and the Kimmel Center; and launching of the Greater Philadelphia Tourism Marketing Corp. to promote the region to leisure travelers.

Whether the center has delivered on its promoters' original lofty promises of additional jobs and economic activity may be open to debate. But it certainly has delivered a lot.

Center City now has more than 200 fine-dining restaurants, three times as many as in 1992, and 225 sidewalk cafes, up from zero.

Chinatown, in the shadow of the center, has thrived and expanded, in part because of increased foot traffic.

By fueling Center City amenities, jobs and activity, the center indirectly helped the resident population grow from 75,000 in 1990 to 88,000 in 2006, putting it behind only New York and Chicago in number of residents living in the central business district.

Tom Morr, president of Select Greater Philadelphia, the economic-development group that works to get businesses to locate in the region, said a cleaner, safer Center City helps attract prospective employers to the whole region. "People who come to the city now come away with a better impression," he said.

Conventions have helped draw leisure travelers as well, said Meryl Levitz, president of the Greater Philadelphia Tourism Marketing Corp. "The Convention Center functions as one of the triggers that helps people consider coming back," she said.

No Philadelphia institution has probably benefited more from the Convention Center than the Reading Terminal Market. In the late 1980s, when the center was being planned, the terminal was so dilapidated that the city considered razing it, including its train shed - now the Grand Hall "wow space" that may be the center's most attractive architectural feature.

"The Convention Center created the investment pool to rescue the building from years of benign neglect," said Paul Steinke, general manager of the market.

Now the market is thronged with four types of customers: residents buying fresh food, lunchtime office workers, Convention Center visitors and workers, and tourists. Its merchants seek out the Convention Center schedule because "they want to plan their purchases around it," Steinke said.

Also pleased are longtime city residents who once worried that the market would be lost and the surrounding area overwhelmed by the huge center.

"I was skeptical before they built the center, especially about what would happen to all the small businesses in that area," said Bob Libkind, a retired Fairmount resident who roams the market two or three times a week buying fresh food.

Today, "I don't see any negative aspects on my neighborhood. It's added to the vibrancy of Center City," Libkind said.

One offshoot is funding for programs to find jobs for people with limited skills and work experience, some of them former welfare recipients. Philadelphia OIC Inc., the nonprofit job-training service founded by the Rev. Leon Sullivan, has used $1.5 million a year in hotel-tax revenue to help more than 3,000 people find jobs in practically every hotel in the region, OIC chief executive officer Bob Nelson said.

And more jobs mean a lower crime rate, he added, "because people who work don't have time to commit crime."

Contact staff writer Tom Belden at 215-854-2454 or tbelden@phillynews.com.