NCAA D1 men's race distance: 10,000 m (10K) at the championship; NCAA D1 women's race distance: 6,000 m (6K) at the championship; D2/D3 distances may differ slightly per division
Why people argue about this
People often assume that the certified playing area in NCAA cross country means it must be a perfectly flat, uniform track like you'd see at a track and field event, but actually, it encompasses varied outdoor terrain over a specified distance, including start, finish, and mid-course points where competitors are supposed to run.