American football field
American football games are played on a rectangular field that measures 120 yards (110 m) long and 53.33 yards (48.76 m) wide. Lines marked along the ends and sides of the field are known respectively as the end lines and sidelines, and goal lines are marked 10 yards (9.1 m) inward from each end line. Weighted pylons are placed on the inside corner of the intersections of the goal lines and end lines.
White markings on the field identify the distance from the end zone. Inbound lines, or hash marks, are short parallel lines that mark off 1 yard (0.91 m) increments. Yard lines, which can run the width of the field, are marked every 5 yards (4.6 m). A one yard wide is placed at each end of the field; this line is marked at the center of the two-yard line in professional play and at the three-yard line in college play. Numerals that display the distance from the closest goal line in multiples of ten are placed on both sides of the field every ten yards.
Goalposts are located at the center of the plane of each of the two end lines. The crossbar of these posts is ten feet (3 meters) above the ground, with vertical uprights at the end of the crossbar 18 feet 6 inches (5.64 m) apart for professional and collegiate play and 23 feet 4 inches (7.11 m) apart for high school play. The uprights extend vertically 35 feet on professional fields, a minimum of 10 yards on college fields, and a minimum of ten feet on high school fields. Goal posts are padded at the base, and orange ribbons are normally placed at the tip of each upright.
- NFL Rules 2012, p. v, 1.
- NCAA Rules 2011–2012, pp. 18–19, 23–24.
- NFHS Rules 2012, pp. 11–12, 13, 28.
- NFL Rules 2012, p. 2.
- NCAA Rules 2011–2012, p. 18.
- NFHS Rules 2012, p. 14.