Fifteen men and women working squeeze boxes in unison may not be unprecedented in Pittsburgh's history, but 15 men and women working squeeze boxes in unison in an empty city swimming pool almost certainly is.

"The visual alone is enough to make your hair stand up," said Steven D. Irwin, an attorney, accordion player and Pennsylvania Securities Commission member.

A strange and charming idea, the Accordion Pool Party yesterday became the event of the summer in Lawrenceville, drawing about 300 people to the neighborhood from around the city.

Master of ceremonies Mike Devine, a Lawrenceville gallery owner, self-described nightlife provocateur and itinerant disc jockey with a show on WRCT-FM(88.3), presided while onlookers sat or milled around the drained pool's perimeter and neighborhood vendors sold refreshments. Musicians played atop the peeling white paint of the pool's floor, while around them people waltzed, danced to polkas and formed a hand-holding, high-kicking chorus line.

The event was planned for a higher purpose: Lawrenceville needs to come up with another use for the Leslie Park pool, south of Butler Street and east of 46th Street, which the city decommissioned in 2003.

Event manager Deb Knox and Susan Englert, who are former colleagues at an architecture firm, decided that staging an event no one would ever forget might rally the neighborhood to pool creative ideas in a series of neighborhood workshops.

"We're calling this a 'springboard' event," said Ms. Knox, an accordion player whose regular band is The Balkan Babes. "I think we accomplished our purpose.

"Afterward, the citizens need to decide how to bring the pool back to some use," she said, adding that residents of the neighborhood will later meet to brainstorm with city planners, Citiparks staff and Councilman Patrick Dowd. "We just don't want it to be nothing."

"You call attention to something and wake it up," said Ms. Englert, an artist, who said she wanted to install something artistic in the pool before getting involved in the accordion party.

"I felt sorry for the space; it needed for something to happen."

She and Ms. Knox hope their party idea becomes a prototype for finding new uses for other decommissioned pools in the city. Since the budget crunch of 2003, the city has closed a dozen of its 31 pools.

The women got grants from the Sprout Fund and Lawrenceville Corp. to pay for party expenses.

But why an accordion party? Because Ms. Knox plays the accordion and knows other players, the idea of a band took off while the women mused over ideas for something that would be memorable and musical.

"Suddenly," said Ms. Englert, "everywhere we went we'd run into accordion players."

By yesterday, about 15 players remained of 25 accordionists who started rehearsing in July. Ms. Knox said she is amazed that so many musicians have devoted two-hour sessions twice a week for two months to practice "just for the joy of being part of this quirky event."

For at least one of them, the quirky event also was a life jacket.

Rado Angelov, who became an impassioned accordionist at age 7 in Sofia, Bulgaria, came to the United States in 1992. While attending Duquesne University, he performed with the Tamburitzans but no longer is part of an organized band. He was resigned to playing alone on the front steps of his home in the Central North Side when he heard about the band forming to play in a pool.

"I didn't think it was that crazy," he said. "I thought it is interesting. And it was inspirational for me. I was kind of like losing it, not even practicing much and this made me ..." He stopped talking as he became emotional.

"We are talking about" playing together beyond the pool party, he said. "I would love for that to happen, to practice and play at events."

The accordion has been the butt of jokes for decades, but "we are all so thrilled to be playing [it] together," said Susan Waggoner, whose button box is a Cajun accordion. She started playing because she fell in love with Cajun music about 30 years ago.

"I'm friends with Deb, and she asked me to participate. I've always respected what a community builder she is, and I thought it sounded like a lot of fun."

The extravaganza of accordions also brought on board the Guinea West African Drum and Dance Ensemble to provide an opening act and the beat for the finale: a world dance party in the pool.

Mona Stratmore, who books the ensemble, said Ms. Englert came to a drum workshop at Your Inner Vagabond, a coffeehouse in Lawrenceville, and "hinted at the pool party event. She said, 'You guys are going to be in this one way or another.'

"I think the concept is really unique, original, funny, a fun thing to make jokes about and really quite a reflection of who Susan and Deb are. They are real characters. They are unstoppable and innovative, and they make things happen. I'm so thrilled they included us."

Mr. Irwin has toured in the cowpunk band, The Surreal McCoys, "with six guys from all over the country.

"But I can't keep this up with my day job, so I had put the accordion down for a bit when I met one of the people organizing the pool party," he said. "They said, 'You gotta do this.' And I thought, yeah, what the heck. It sounds so crazy and so good."

Others who live in the neighborhood said they, too, were entranced by the idea.

"I'm really excited the pool is being used for something that's so much fun and I'm excited to see what else it might be used for," said Rebecca O'Connell, a resident for 16 years.

John Burke, one of yesterday's players, said being part of a "wall of sound" band was "a gas."

"I'm stoked and anxious to find other outlets to perform. The response from people has been phenomenal. It's kind of hip in a strange and nouveau way."