Other parade participants included the Lakota West High School band, the only Ohio high school marching band to perform in this year's Rose Bowl Parade, and Team Lachey, winners of the NBC reality show "Clash of Choirs."
Family members of Reds broadcaster and pitcher Joe Nuxhall, who passed away in November, rode in a vehicle dedicated to The Ol' Left-hander.
The parade route proceeded south on Race Street to Fifth Street, then turned east past Fountain Square. It concluded at Broadway, just two blocks from Great American Ball Park.
The parade caravan arrived at Fountain Square at around 11:30 a.m. ET with fire engines blaring sirens, bagpipers and roars from the sea of red-clad revelers who braved a steady light rain.
"Opening Day still means a lot here," said James Price, 27, of Flemingsburg, Ky. "It's the tradition of Cincinnati being the first professional team. This is a great crowd for the weather."
Reds outfielder Ken Griffey Jr., who grew up in Cincinnati, remembered fondly attending Opening Day while his father, Ken Sr., was playing for the Reds.
"The main thing was we got out of school early," Griffey said. "We never got out early enough for the parade, but I remember hoping for a win so we could go into the clubhouse. If they lost, we'd have to wait outside, which wasn't fun. Opening Day means a lot to the fans here."
John MacDonald of nearby Monroe, Ohio, who frequently attends Opening Day, echoed the optimism of many Reds fans in attendance.
"I always the love the crowd and the excitement of starting a new baseball season," he said. "I think the team's going to be good. We have a good shot at the playoffs. [Reds manager Dusty] Baker brings a winning attitude."
Findlay Market is the oldest surviving municipal market house in Ohio. The inaugural Findlay Market Opening Day Parade took place in 1920 to celebrate the Reds' victory over the White Sox in the 1919 World Series.
Opening Day in Cincinnati is an event like no other, with many downtown bars and restaurants opening in the early morning and filling to capacity by lunchtime.
"This is the biggest day of the year here," said Baker. "I just hope the fans that come here today will come back. We're trying to create some excitement here, so we don't just have one Opening Day."