Bike riders will be damp, dirty and mosquito-bitten when they arrive this afternoon at Point State Park.

But many of the more than 80 participants in a Washington-to-Pittsburgh cycling tour say they have made memories and friends that will stay with them for the rest of their lives.

"It's a life-changing experience," Charlotte Roberts explained Thursday night after she and her husband, Gary, arrived in Confluence, Somerset County. "You push yourself until you think that you can't pedal any further," the 63-year-old Hermitage resident said. "Then you call on something deep inside and off you go."

When she and her husband rode out of Confluence early yesterday morning, they and their companions had about 90 miles of trail left to cover over the next day and a half. Their group, the Venture Outdoors 250 Bike Tour, left Washington, D.C., Saturday.

They will meet up today near the Riverton Bridge, which links Duquesne and McKeesport, with "PNC Legacy Trail Ride" cyclists. Those relay riders left Washington yesterday afternoon with a congressional proclamation honoring Pittsburgh's 250th birthday. The relay teams are scheduled to travel the more than 330 miles of trail between Washington and Pittsburgh in 24 hours.

Both groups will take part -- along with local bike riders and walkers -- in a parade down the Boulevard of the Allies to Point State Park. Cyclists and marchers are scheduled to arrive there between 1:15 and 2 p.m.

Point State Park will be the focus of a full day and evening of activities. The "Birthday Blow-out" will climax at 10 p.m. with "Imagine Pittsburgh" fireworks. The Colcom Foundation is principal sponsor for today's events.

Completion of the Great Allegheny Passage, the name given to the portion of the hiking-biking trail that links Cumberland, Md., and Pittsburgh, is one of the signature projects of the city's birthday celebration.

"Pittsburgh 250," the umbrella organization overseeing the commemoration, was created by the Allegheny Conference for Community Development. Michael Langley, chief executive officer of the conference, is one of the cyclists pedaling to Pittsburgh and camping out most nights along the way. He is riding one of 25 customized, individually numbered black-and-gold trail bikes built for the celebration.

"I think the trail ride is a metaphor," Mr. Langley said Thursday night. "It is a wonderful experience. I'm stunned by the beauty we possess in Western Pennsylvania."

"On this trip we have young, smart professional people coming to Pittsburgh," he said. "They are discovering that it is a great destination and a great place to build a future."

Riders on the eight-day trip come from 12 states and Canada. They range in age from 20 to 76. They include 24 women and 60 men.

Many agreed the C&O Towpath, linking Washington and Cumberland, was tough going. They faced rain, mud and mosquitoes. Conditions improved, however, once they crossed the Mason-Dixon Line on Thursday morning.

"I would never want to give up mountain biking, but I hope this will the first of many [trail bike] tours," said Jen Sands, 24, of Alexandria, Va. "This has been a great day -- the scenery is beautiful, and the trail condition is perfect."

"I think you really mature as a human being on a trip like this," said William Luff, 20, of Natick, Mass.

"You mature all right," agreed Lindsay Dragan, 21, of Shadyside. "I think I've taken five years off the life of my knees."

"Yesterday was the most miserable day I've ever had on a bike," said Scott Person, 36, of Alexandria. "But you can't pick and choose days to ride when you are on a tour. Today the scenery has been beautiful. It's changed my opinion of Western Pennsylvania."

Frank Schroeder, 66, of Land O' Lakes, Fla., lived in Pittsburgh for two years in the mid-1960s when he worked for Jones & Laughlin Steel. In recent years he has cycled all over the country, mostly with a group of friends from Missouri. He said he already was looking forward to doing the Washington-to-Pittsburgh trail again, this time with his biking buddies.

Michele Forte, 37, is a Bentleyville native who now lives outside Washington and serves in the Air Force as a JAG lawyer. The difficulty of the trip depended on your perspective, she said.

"The mud made the first part of the ride a little frustrating," she said. "But my last summer 'vacation' was in Baghdad."