Soap box derby in front of a large crowd with American flags flying, unidentified location. According to Wikipedia, "In the wake of the first car races, local youth auto races took place in the US at a very early stage. In 1914 the motion picture Kid Auto Races at Venice starring Charlie Chaplin was shown in the cinemas." Larger, national competitions came into existence in the 1930s. Although the sport still exists today, the 1950-1960s were its heyday. Since many of the the men in this photo are wearing boaters, this is thought to be in the 1+10s-1920s.