Marathoner... Benoit
XC/Track... Jennings
Overall... Kastor
Benoit was argubly more successful than Kastor in the marathon. Oly gold for Benoit, but it is a very competitive era than it was 20 years ago. Jennings won WC gold twice (and many, many US titles) and medaled on the track, but didn't have the marathon successes of Kastor. So given Kastor's success in the marathon (fast times, Oly bronze, wins at Chicago, London), success in cross (2 WC medals, multiple US titles), AR in the 10k on the track, and road successes from 5k to half marathon and beyond, I give her the edge as best American female distance runner overall.