Tunnel Hill 100K
Race Day Weather
Comfortable temps, moderate wind
Mild 55°F temps at gun time mean comfortable early miles without overheating risk. Moderate winds around 13mph may affect pacing on open sections of the course. Moderate humidity at 75% is worth noting for effort level, especially in later miles.
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Race Info
The Tunnel Hill 100K covers the same Tunnel Hill State Trail out of Vienna, Illinois as the marathon and longer ultra fields, running the full 50-mile out-and-back loop plus an added southern spur before finishing at Vienna City Park. Like the other distances it runs on a crushed-limestone rail-trail bed with a grade under 2 percent, crossing the trail's namesake railroad tunnel twice. The event carries an IAU Bronze Label and is USATF and World Athletics certified.
