Drawing on an idea that has gained popularity across the nation, Travelers Aid of Pittsburgh will stage a citywide treasure hunt next month to raise money for its programs providing public transportation to low-income and at-risk residents.

The Pittsburgh Transit Treasure Hunt on Sept. 19 will send teams of up to four players scurrying to follow clues and solve riddles based on city landmarks and history. Rule one: The players must use Port Authority buses to travel.

The hunt will begin at noon at the Grant Street Transportation Center at 11th Street and Liberty Avenue and fan out to the rest of Downtown and the South Side, Strip District, Lawrenceville, Bloomfield, the Hill District and Oakland.

Travelers Aid is hoping to attract 150 or more participants for its first-ever hunt, said Greg Williams, events coordinator for the agency.

He said the idea stemmed from similar events that have surged in popularity in other cities in recent years.

One of them, the Great Urban Race, has events in 20 cities this year culminating in a national championship in New Orleans in November.

Players in such events are given riddles and clues to guide them to a certain place, where they answer a question, obtain an item or take a photograph.

In Pittsburgh, the players will be sent to a neighborhood and have three hours to view landmarks and answer riddles. Mr. Williams said the questions won't be easy.

"Some of the clues are obvious, but a lot of them are going to require second- and third-tier thinking," he said.

In addition to raising money, the events are "a way to highlight urban centers that are being redeveloped and take advantage of cultural, historic and architectural landmarks," he said, adding that the planning for the hunt has heightened his own appreciation of the city.

Organizers think the event will be especially appealing to college students who have just moved here.

After the hunt, participants will return to the starting point for a ticket auction, awards, refreshments and live music from the group Timbeleza. The top three finishers will receive "high-end" electronics prizes, Mr. Williams said.

A United Way nonprofit organization established in 1921, Travelers Aid helps disadvantaged residents get to medical appointments, new jobs, day care and other necessities.

"We utilize almost exclusively public transportation for our programs in order to minimize overhead and maximize the impact of those in need," said Robert H. Lindner, executive director. "We are a little-known or -advertised agency working quietly behind the scenes to keep Pittsburgh moving."

"This event sheds light on a real need in our community that public transportation fills each day," Port Authority spokesman Jim Ritchie said. "Port Authority is thankful for the services provided by Travelers Aid of Pittsburgh and the support it receives through the United Way."

Registration is $25 for adults (with a $5 discount for registration by Thursday); and $10 for those older than 55 or ages six to 21. Participants can register at travelersaidpgh.org (click on news/events) or by calling 412-281-5474.

Partners in the event are Port Authority, the Pittsburgh History & Landmarks Foundation and Venture Outdoors.

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