ONE OF THE truly terrific things about being an American is participating in the discovery and rediscovery of different places in our nation. In the last few years, we Americans have "discovered" Vermont, Colorado, California, the Sun Belt, older cities and small towns. The most recent discovery is Pittsburgh, Pennsylvania.

Pittsburgh, called the "City of Champions" after its baseball Pirates and football Steelers, has never previously come infor too much lionizing. The only major metropolitan area in the United States that is losing population, Pittsburgh was described by James Parton over 100 years ago as "hell with the lid off." The home of U.S. Steel has not inspired romantic ballads like New York or San Francisco or even Miami. But now Pittsburgh is hot.Brawling, blue-color Pittsburgh is much more than the professional sports capital of the country.

Demographic studies remind us regularly that we are becoming more and faster a nation of white-collar employees. The steel industry, with its premium on strong arms and a muscular work force, is in decline. Coal is always a crash program away. But Pittsburgh is still very much today a city of steelworkers and boilermakers, the latter being an aperitif rather than an occupation.

But understand well: Pittsburgh is no city of Archie Bunkers. This city, which is 80 percent white, has had two baseball heroes in the last 15 years: Roberto Clemente and Willie Stargell -- a black South American and a black North American.

Sociologists tell us that newer connumities lack most of all a sense of community, a shortage of neighborhoods. Pittsburgh is and always has been a series of neighborhoods assembled around some very large mills.

Maybe it's just an extension of the national nostalgia rage. Maybe it's some deserved recognition for what this Mill Town has accomplished in downtown renewal and the progress its citizens have made in cleaning up the air. Or perhaps it's the totally understandable yearning on the part of the rest of us, who left neighborhoods and roots, to feel again that spirit of community and home-town pride that is Pittsburgh.

Whatever it is, this shot-and-a-beer town, where the Monongahela joins the Allegheny to form the Ohio, is the object of a lot of envy this weekend. And not simply because its Steelers are in the Sugar Bowl.