Blood Rock 100

Blood Rock 100 is an annual trail ultramarathon held at Oak Mountain State Park, located approximately 20 miles south of Birmingham, Alabama. The primary event is a 100-mile race, measuring 101.79 miles, which begins on a Friday morning. Runners are allotted 44 hours to complete the distance. Typically held in early December, participants may encounter cold, wet, or variable weather conditions throughout the more than two days and nights spent on the course. Southeastern Trail Runs is the organizer, and a 50-mile race option is also available. The 100-mile course consists mainly of singletrack trails (92.84 miles), supplemented by 7.74 miles of car-free gravel roads and just 1.18 miles of pavement. The route involves a total elevation change of 17,512 feet, emphasizing endurance over speed. The challenge lies in navigating continuous hills, uneven terrain, time cutoffs, and exhaustion. The start and finish lines are situated near the cabins by Tranquility Lake, providing convenient lodging for some participants close to race headquarters. Blood Rock is designated as a UTMB Index race, and recent years have seen over 100 participants in the event.