Originally field archery split from target archery in 1939 because the participants wanted to practice in hunting situations at unknown distances and field archery was born with shots at ranges of 20 feet to 100 yards all unknown.. Later with the advent of sights the yardage was changed to known and the distance shortened to 80 yards as a maximum.. A field course is great practice even for the instinctive shooter like me, knowing the yardage isn’t an issue but hitting the target is.. Also for those who may not know this each 14 target set has 10 targets that you will shoot all 4 arrows from the same position. There will be 3 more targets that are called walk-ups and you get to move closer to the target after each shot. That leaves 1 target where you will shoot all your arrows from one distance but will move laterally between each shot. This target is called the 35 yard fan. The 3 walk-ups are 80-70-60-50 yards, 45-40-35-30 yards and 35-30-25-20 feet. That last one is called the Bunny target. The other two are known as the 80 yard walk-up and the 45 yard walk-up. The targets where you shoot all 4 arrows from the same position are at the distances 15, 20, 25, 30, 40, 45, 50, 55, 60 and 65 yards. So the farthest distance, from which you will shoot all 4 arrows, is 65 yards. Most ranges are not on flat ground and often there are shots both up and down hill and plenty of side hill shots as well. Then there is the Hunter course with similar ranges except at odd distances
I often take my more advanced students to the range here in Waco and we walk the course shooting from both known and unknown distances..