Tunnel Hill 100 (IL)

The fastest hundred in the world. A dead-flat, out-and-back crushed-limestone rail-trail through the Shawnee National Forest that has produced five world records, including Camille Herron’s untouched 12:42:40 open women’s 100-mile world record — and a genuine shot at a first, or fastest, 100-mile finish for everyone else.

Quick facts

Location: Vienna City Park, 302 E. Vine St, Vienna, IL (start/finish)
Date: November 14, 2026, 7:00 AM start
Distance: 100 miles — two out-and-back 50-mile loops, 30-hour cutoff
Website: tunnelhill100.com
Contact: durb417@gmail.com — RD Steve Durbin, Durbin Race Management
Registration: Via UltraSignup/RunSignUp; the field is capped and fills. A Western States 100 qualifier and IAU Golden Label 100-mile race.

Course description

A converted rail corridor on the Tunnel Hill State Trail through the Shawnee National Forest of southern Illinois: smooth, crushed-limestone surface, tree-lined nearly the entire way, with a consistent, gentle 2% grade and no technical footing to speak of — no rocks, roots, or water crossings. From the start/finish at Vienna City Park, runners head south to a turnaround near the Cache River Wetlands Center, then north past Vienna to a northern turnaround, completing a 50-mile out-and-back; 100-mile runners repeat the full loop a second time. The route passes through the iconic Tunnel #1, a 543-foot limestone passage that gives the race its name, along with several historic wooden trestle bridges spanning bluffs and creeks. There is only one major road crossing on the entire course.

Elevation change

Elevation on the trail ranges from about 340 feet at the southern end near Karnak to 680 feet at Tunnel Hill itself, producing a gentle, unrelenting 2% grade rather than any real climbing — one of the flattest, fastest certified 100-mile courses in the world, which is exactly why it keeps producing world records.

Aid stations

Aid stations are spaced roughly every 5 miles along the trail, with two additional drop-bag locations beyond the start/finish (Karnak and Tunnel Hill) that 50-mile runners pass twice and 100-mile runners pass four times each. The unmanned Breeden Trestle water stop (mile markers 31.5, 45.1, 80.9, 95.1) has jugs of water only — no cups anywhere on course, so runners must carry their own containers. Stations are stocked with Tailwind, bananas, oranges, chips, candy, egg sandwiches early and wraps, boiled potatoes, and soup later, plus hamburgers and hot dogs at the Vienna Park station.

Special conditions & average temps

Mid-November in southern Illinois is deliberately chosen to avoid summer heat and humidity — expect cool, sometimes cold conditions, with a real chance of rain, wind, or an early cold snap (a freak snowstorm hit the 2022 running). The trail closes at dark to anyone not in the race, and cutoffs are strict: 100-mile runners must begin their second 50-mile loop within 15 hours of the start, with no grace period on the 30-hour overall limit.

Registration deadline & how to get in

Registration opens well in advance through UltraSignup/RunSignUp and the field — capped for course and aid-station capacity — routinely sells out. No qualifying race is required to enter, but Tunnel Hill itself is a Western States 100 qualifier and an IAU Golden Label 100-mile race, drawing elite fields chasing records alongside first-time-100 hopefuls chasing a buckle on the fastest course in the sport.

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Tunnel Hill 100 (IL)

Quick facts

Course description

Elevation change

Aid stations

Special conditions & average temps

Recent results — top 3, men & women

2025

2024

2023

Registration deadline & how to get in