<P> The Cincinnati Riverfest is an annual festival that has taken place Labor Day weekend since 1977 . The highlight of the event, the fireworks display at 9: 05, is one of the largest in the Midwest . </P> <P> The fireworks display was first organized in 1977 to celebrate the 10 - year anniversary of rock and roll radio station WEBN (frequency 102.7). This has now evolved into an all day event is held every year on the day before Labor Day . The corporate sponsors are WEBN and Western & Southern Financial Group . Riverfest is filled with many activities and ends with a gathering on the banks of the Ohio River in Cincinnati, Ohio, Covington, Kentucky, and Newport, Kentucky to watch a half - hour fireworks show set to an underscore heard on WEBN . The fireworks are provided by Rozzi's Famous Fireworks Inc . The show attracts nearly 500,000 to the area every year . Over 2,500 boats jam the river to get a front row seat for the show, and the river is patrolled by the US Coast Guard, Kentucky Department of Fish and Wildlife, Ohio Department of Natural Resources, and local units from Cincinnati, and Covington . The river is normally closed between the Roebling Suspension Bridge and the Big Mac (Interstate 471) bridge . </P>

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