National Hunt or Steeplechases are usually run over longer distances than flat races, with races being between 3.2km and 8km. Races are run over a series of obstacles including brush fences, stone walls or ditches. The horses competing in these races are usually larger and older and are built for stamina and speed. Horses start off at the age of three in hurdles races which are over smaller hurdles and shorter distances before graduating onto chases which are of longer distance and with larger obstacles. There are usually no starting stalls in National Hunt racing, the horses line up in a row and are flagged off by the starter.