As a midwesterner, I've got two nominees:
1) Missouri-Columbia (on campus version). Ran a District V meet there in the late 80's. This was the era when only two teams advanced from a district(none of this 31-team field stuff we see today), and Iowa State was a dominant force on the scene. I have memories of passing a red and gold clad Cyclone who was face down and prone on the last hill in the 9th kilometer. Iowa State came in as the top ranked team, but did not advance as a result. I remember running a shade over 33 minutes, but finishing something like 32nd. And the weather was perfect. Ouch
2) Indiana's old 10K at the golf course--this was the one that took you up towards the clubhouse twice. After the second trip through the infamous "sinkhole" you had the long grind to the top at about 8K. It's been 15 years, and the pain is still quite vivid in my mind. I also have memories of an NCAA meet from the early 80's, and Spivey led through much of the race before the hills took him apart. The trainers had to scrape him up with a spatula when he hit the chute.