Braving torturous traffic getting there and a stubborn haze throughout the day, a throng of more than 50,000 took what seemed like a neighborly stroll across the Chesapeake Bay Bridge yesterday.

And, for the first time, runners dashed across the bridge in a 10-kilometer run that organizers hope will become an annual event.

The brilliant springtime colors of this 11th annual bridge walk were muted by the haze, but that didn't stop families with babies in tow and retirees with well-worn walking sticks from crossing the east span of the bridge, from Kent Island to Sandy Point, the narrowest point of the bay.

They came from the District and Baltimore, from the Eastern Shore and from Northern Virginia, and by noon all three parking lots were full. Thousands of prospective walkers were turned away, some after sitting for hours in traffic.

Why do so many come so far every year to take a 4.3-mile walk across a bridge?

"Well, sir," said Walter D. Ward, 74, a retired D.C. policeman who walked the distance yesterday for the fourth time, "it's just to show folks that I can."

Ward, clad in a Redskins windbreaker and a wool cap to match, said: "I'm not getting any younger, you know. It took me two hours to walk it this year. And the downhill was the best part."

"The other times I cross in my car I have to pay $1.25 to do this," said Matilda Sause, 78, "but now I can cross for free."

The walkers were delighted with the ships crossing beneath them, at the eerie swaying of the span when the wind gusted, and at a police hovercraft hotdogging for the crowds in the shallow waters off the western shore. ("I'm sure that's not in the training manual," said one onlooker as the hovercraft carved neat curves in the water, sending up spray.)

"It's beautiful," said Lam Van Le, a student who lives in the District and whose teacher recommended the walk to him. His companion, Patricia Santamarianova, a student visiting from France, nodded her agreement. "We want to come back next year if we are both still here," she said.

Traffic on Rte. 50 near the bridge was fierce yesterday, according to officials of the Maryland Transportation Authority who sponsored the walk.

Although the walk attracted about the same number of people as in past years, they said, people arrived and filled the parking lots earlier in the day. Some latecomers waited hours for buses that shuttled between the parking lots and the bridge.

The walk began at 9 a.m. and ended at 4 p.m. By 5:15, the east span was reopened to traffic.

The walk has become a fixture on the outdoor calendar, as much an April tradition as taxes for some. But like the best traditions, it can grow and change, and yesterday the walk was embellished a little.

Starting just after 8 o'clock in morning, while most walkers were preparing to drive to the bridge, 2,750 runners began their trek.

The winner was Brian Palmer of Annapolis, a 23-year-old research technician from the Smithsonian Institution's Environmental Research Center with ostrich legs and a gait to match.

He crossed the finish line in 32 minutes 31 seconds -- 15 seconds faster than John Roemer, who led for the middle two-thirds of the way but faded in the end -- and let fly a victory whoop.

The gangly Palmer, who sports the hint of a mustache, a stubby pony tail and a silver earring, told reporters at the finish line that although he had finished first in cross-country races at Bates College in Lewiston, Maine, this was the first road race he had won.

Palmer and the first-place woman, 37-year-old Pat O'Brien of Annapolis, a registered nurse, are members of the Annapolis Striders running club.