This video was made to provide a rough idea of what vintage racing entails. All races are held on "road courses", not circle tracks like NASCAR. Every track is different with its own quirks and nuances. Some are relatively short and curvy (~ 1.5 miles per lap), and some are long and fast (~2.5+ miles per lap). This video was filmed at Texas World Speedway in College Station, TX. It is a 2.9 mile - 15 turn road race track.
Most vintage races last approximately 20 minutes. While one group is out racing, the next group is "gridding up" inside the paddock. As soon as one group finishes, the next group is ushered out onto the track behind the pace car. It is common for each group to race twice per day, with about 12 races in total.