Date
14 Mar 2027
Distance
20 Mile
Surface
Road
The Fission 20 is a 20-mile road race in Berkeley, Gloucestershire, and is a popular option for runners preparing for a spring marathon. The course is known for being flat and fast, making it well suited to marathon-pace practice and longer training efforts in the final build-up to race day. It is often used as a key benchmark race, giving runners a clear indication of fitness ahead of their target marathon.
