No Stage Races or Rogaines are listed here. The Hi-Tec Series probably the best known sprint race series, with races near major metro areas. Well run, good first exposure.
Dates vary by city.
The Odyssey One Day run very good races in VA . May. Texas Sprint AR runs a series of one day sprints in Texas and Oklahoma including the Houston Wild Onion. The Rattlesnake Challenge several one-day races in Texas. The Great Mississippi River Series several one-day races in Illinois. Well run race.