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Thames Ring 250
Wednesday, April 21, 2027 · Reading, United Kingdom
About this race
The Thames Ring 250 is actually closer to 256 miles, beginning and ending at Streatley-on-Thames on a large loop of southern England’s rivers and canals. The full race commences on a Wednesday morning, giving runners 100 hours to return. The series also features a 150-mile race from the same start to Nether Heyford and a 100-mile race from Nether Heyford to the finish. It is a trail and towpath ultra, not a mountain race, but the distance, sleep deprivation, night running, and navigation make it considerably more challenging than its flat profile indicates.
The route proceeds anti-clockwise along the Thames, up the Grand Union Canal, then returns toward the Thames via the Oxford Canal, utilizing mostly canal paths, riverside paths, rural footpaths, and some urban sections. Runners are provided with maps and GPX files, pass checkpoints approximately every 25 miles, and carry sufficient food and kit to manage between official support points. GPS trackers allow spectators to follow the race. Sleeping tents are available after 75 miles for the 250 and 150-mile runners, and drop bags are transported through the checkpoints for the longer distances. The full race has an average finish rate below 50 percent, a statistic that speaks volumes; it was also the first UK race of this distance and, for many years, the longest non-stop race in Europe.
Start location
Streatley-on-Thames
Reading