The race and its many other events has runners hoofing it through parts of Cincinnati, Mariemont, Fairfax and Northern Kentucky and will affect traffic throughout the weekend.
The Flying Pig and the accompanying Queen Bee Half-Marathon are two of Cincinnati's biggest annual events, attracting more than 40,000 people over three days.
Flying Pig 2021: Road closures and traffic detours cincinnati.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from cincinnati.com Daily Mail and Mail on Sunday newspapers.