Sand Hill
I ran the marathon at this race many years ago. It's very hilly, and starts at 6 or 7 p.m. and is always super hot. The out and back section would be really easy to just turn around early on in the dark, as it wasn't manned (at least not back then) I'm only skeptical because the course record for the marathon used to be held by 2:17 marathoner who ran 3:07 or something at the Boogie. The race is not a record breaking kind of course.