Pittsburgh will celebrate its 250th birthday on Oct. 4 with one of the largest fireworks displays ever in the region.

The city will be the birthday cake, said Zambelli Fireworks chairman George Zambelli, and the skyline will be the candles.

Fireworks will be shot off from the tops of the U.S. Steel Tower and other skyscrapers Downtown, as well as from the West End Bridge and barges in the three rivers.

"There isn't a venue in the U.S. that matches Pittsburgh," Mr. Zambelli said yesterday afternoon, gesturing toward the city skyline while standing on board the Gateway Clipper Fleet's Majestic at Station Square.

Officials, including Pittsburgh Mayor Luke Ravenstahl and Allegheny County Chief Executive Dan Onorato, held a news conference on the Majestic to announce plans for celebrating Pittsburgh's 250th anniversary during the second half of 2008.

Many people Downtown were startled when organizers set off a few fireworks yesterday at noon to give Pittsburghers a taste of what to expect in the October show.

The free community celebration at Point State Park will include live music and a riverboat flotilla featuring a variety of vessels, including dragon boats, as well as "Imagine Pittsburgh" -- the name for the giant pyrotechnics display scheduled for that evening.

The fireworks show will have the most launch sites ever produced in the United States, according to organizers.

The celebration will also mark the end of the PNC Legacy Trail Ride, a 335-mile biking journey along the Great Allegheny Passage from Washington, D.C., to Pittsburgh and Point State Park.

Currently, the biking and hiking trail ends in McKeesport, but Mr. Onorato said yesterday that it will reach Point State Park in time for the Oct. 4 celebration.