Hurdles are made to fit inside each of the eight lanes on the track. International and Olympic tracks feature lanes that are 48 inches wide, while each college and high school lane is 42 inches wide. Most hurdles are adjustable in height; made out of steel, aluminum or wood. Setting the height depends on the event. Short races, such as the 55-meter or 60-meter hurdles, use 39-inch heights for boys' high school, 42-inch for men's college and international, and 33-inch heights for girls' and women's events. Longer races, such as the 400-meter hurdles and steeple-chase, feature lower heights -- 36 inches for male athletes and 30 inches for female.