the stp 500 is a monster energy nascar cup series race. it is held every spring at martinsville speedway, it was first run in 1950 and held in conjunction with the camping world truck series race the previous day. goody's powder sponsored the race from 1996 to 2002 and again in 2007 to 2012. the race is first of two races held at the racetrack, with the other one being the first data 500 in november.