Sebring International Raceway was originally an Air Force training base during World War II, but in the post-war years the base was bought from the US government and transformed into the cathedral of American endurance racing that it is today. Sebring hosts a twelve hour event in March that serves as one of the benchmark races to determine who has what it takes to win the IMSA WeatherTech SportsCar Championship.
Photo courtesy of Brian Cleary/Getty Images

Billed as the “Greatest Spectacle in Racing”, the Indy 500 has been a cornerstone of American sports for over 100 years and serves as one of the biggest races in the world, raking in nearly 300,000 spectators on race day. Average lap speeds of over 220 miles per hour also make this race the fastest circle-track event on our list.
Photo courtesy of IndyCar Series

Most sanctioning bodies save their biggest race for the end of the season or the mid way point. NASCAR however hosts The Great American Race to kick off the NASCAR season in style in mid February. The 500 miles long Daytona 500 is preceded by nearly two weeks of preliminary events all collected under the banner of Speedweeks, so there is always something worth watching.
Photo courtesy of Brian Lawdermilk/Getty Images

Originally a mainstay of the F1 tour, the Long Beach Grand Prix is now hosted by IndyCar and still remains a race that defines American street circuit racing. Held right next to the harbor, Long Beach is one of the first handful of races in the IndyCar season, but its prestige and winner’s purse is exceeded only by the Indy 500 held in the month of May.
Photo courtesy of Acura Grand Prix of Long Beach

Daytona hosts two of the biggest events in motorsports and they occur scarcely a month apart. The worldwide motorsports season unofficially kicks off in mid January, when the IMSA WeatherTech SportsCar Championship heads down to the winter haven of Daytona Beach for a grueling day long test of man and machine.
Photo courtesy of AP Photo/John Raoux

This October race at Michelin Raceway Road Atlanta offers plenty of action for racing enthusiasts, including night racing, high-tech cars that reach speeds of 200 miles per hour on the backstretch and a track with plenty of spectacular viewing opportunities.
Photo courtesy of Motul Petit Le Mans

Nicknamed "the Granddaddy of Them All," the Knoxville Nationals is considered the premiere title in sprint car racing (with the highest paying purse), held on the second Saturday in August at the Knoxville Raceway in Iowa. 
Photo courtesy of Knoxville Raceway

This triple header racing weekend has become one of the top-ranked events on the NASCAR calendar, as Watkins Glen International hosts a 90-lap, 220.86-mile stock car race. Between races, fans can take a hot lap in a Toyota Pace Car, watch pit crews set up their stalls and enjoy a weekend of camping at this scenic road course.
Photo courtesy of Robert Laberge/Getty Images

The Bojangles' Southern 500, scheduled each Labor Day Weekend, is known as one of NASCAR's oldest superspeedway races and a crown jewel on the annual calendar. This Monster Energy NASCAR Cup Series race takes drivers around the Darlington Raceway track 367 times – a total of 501 miles.
Photo courtesy of Jasen Vinlove-USA TODAY Sports

IMSA racing is often at its best at the WeatherTech Raceway Laguna Seca, where drivers must face the Corkscrew, a blind drop turn late in the lap, as well as the single apex Andretti Hairpin at Turn 2.
Photo courtesy of Mazda Raceway Laguna Seca