Hillingdon 20

Hillingdon 20, formerly the Finchley 20, is the UK's longest-running 20-mile race. Based at Hillingdon Athletic Club in Ruislip, it offers a challenging, hilly 20-mile road course and serves as an ideal build-up for London and other spring marathons. The event is well-supported with a marshalled route, chip timing, and professional medical cover, run by an experienced team of runners.

Expect a lively atmosphere with over 70 spectators cheering along the way, plus changing rooms, showers, and refreshments at the Hillingdon AC clubhouse. It also hosts the Hertfordshire 20 mile Championships, with cash prizes for top finishers and age-category prizes. Free parking nearby, and the nearest rail is Ruislip Station. Visit the organization's website for the most recent information.