The barrels for "barrel racing" are always arranged in a triangle. It is also known as a cloverleaf pattern, because it resembles the shape of a clover. Competitors gallop up to the barrels and ride round them as fast as possible. The horses need to be very agile in order to be able to manage the tight turns while going very fast. If a competitor knocks over one of the barrels, they lose the race. The event was primarily invented for cowgirls, and to this day it is almost exclusively women who enter.