DENVER — There were balloons and free cookies, stickers and speeches on Tuesday to mark the 30th birthday of a pedestrian mall that runs through the heart of this city’s downtown. The mayor read a proclamation, office workers hustled past with late-morning lattes and a few homeless men shadowboxed with the celebratory red-and-white balloons.

So goes life along Denver’s mile-long 16th Street Mall.

For all its vitality and new development downtown, Denver is still a city in search of an icon. It has no Golden Gate Bridge, no French Quarter, no Empire State Building. The snow-capped Rockies float like a mirage off to the west, far beyond the city limits. What Denver has, instead, is the mall.

Unlike attempts by other cities to revive their downtowns by closing major streets to traffic, Denver scored a major success and created a new public square with its 16th Street Mall. It draws map-carrying tourists, badge-wearing conventioneers and white-collar workers, all weaving through a sprawling circus of buskers and petitioners, transients, sunglass sellers and street artists. Each year, about 16 million people ride the free shuttle buses that carry people along it.