Did you know that the highest recorded race speed for a Thoroughbred was set at Penn National Race Course in Grantville, PA on May 14, 2008?
According to the Guiness Book of World Records, this feat was set by the 2-year old filly Winning Brew — clocking a speed of 43.97 mph (70.76 km/h). This blistering pace was covered over a quarter-mile (402 m, 2 furlongs) in 20.57 seconds.
The record for 1.5 miles (2,414 m) stands at 37.82 mph (60.86 km/h) by 3-year-old Hawkster with a time of 2 min and 22.8 seconds. However, this occurred on West Coast at Santa Anita Park in Arcadia, CA on October 14, 1989.
Original news source credited to: http://www.guinnessworldrecords.com/world-records/fastest-speed-for-a-race-horse/