Trail Running calendar near Harwell 2025-2026

The Allsorts Tinkley Gate Santa Dash is a festive, family-friendly running event held at the scenic National Trust Tinkley Gate site in Woodchester, Gloucestershire. Participants can choose between a 5km off-road trail or a shorter 2.5km route, suitable for younger runners. The event welcomes runner..

Winter Downs 200 is a 200-mile trail race staged by Centurion Running from 10–14 December 2025. The loop traces the North Downs Way, Vanguard Way, South Downs Way, Wayfarers Walk and St Swithuns Way around the South, with 96 hours to finish the single-stage course, live tracking, and crew access at..

Mince Pi Run - races of 2 decimal places is a 14 December 2025 off-road event at Shalford Park, Guildford. Participants choose from 3.14 to 31.4 miles (1–10 laps) on a scenic, mostly flat course with one or two hills. A Pi marathon option and a 1-mile Pi-shaped fun run for young children are offered..

The Salcey Forest Christmas 10K, 5K & Junior Fun Run is a festive trail running event held in Salcey Forest, Northamptonshire. Set amidst beautiful, tree-lined woodland paths, the race offers a virtually flat, mixed-terrain course that can be occasionally muddy. Participants can choose between a 10K..

The Chelmsford Brew Co 12k's of Christmas, run & rum is a festive, social running event held at the Chelmsford Brew Co venue, including the Voodoo Keller Bar and the brewery tap room. The 12-kilometre course features a basement-start climb, a tap-room checkpoint, and a finish in the Voodoo Keller Ba..

The Slow and Dirty is a festive-themed 19-kilometer trail race held in Sturminster Newton, Dorset, following a level, hard-surfaced route along a former railway line known as the Somerset and Dorset. Despite its name, the course is fast and clean, offering a scenic run through the Stour valley, pass..

The Die Hard Christmas Marathon and Half Marathon is a festive running event taking place on December 24, 2025, at Caldecotte Lake in Milton Keynes. Participants can choose between a full marathon, consisting of 7.5 scenic laps, or a half marathon with 3.5 laps. The event features a supportive atmos..

The Winter Woolly 10km is a popular trail running event held annually on December 24th at Elstree School in Upper Woolhampton, Berkshire. Now in its sixth edition, the race features a scenic multi-terrain course covering 10 kilometers with 80% off-road paths, including lanes, footpaths, trails, wood..

The Plain Crazy Winter is a challenging 12.5-mile trail run held in Warminster, known for its hilly, cold, and scenic course that can be windy, snowy, and desolate. The event supports The Royal British Legion Poppy Appeal and offers prizes for top male and female finishers across various age categor..

Winter X is a mid-winter trail-running challenge in the Meon Valley, Meonstoke, Hampshire. Runners choose from four distances: 10km, 30km, 50km, or 70km, following public trails including the South Downs Way, with short road connections. The four out-and-back legs start at The Meon Hall, with checkp..

The Knacker Cracker is a challenging 10K trail race held annually at Box Hill, Surrey, starting from Denbies Vineyard near Dorking, UK. Known as "Britain's toughest 10k," the course features a demanding route with 473m of ascent and 335m of descent over rough, steep, and often slippery terrain. The..

The Fitstuff G3 Series No.1 is a trail running event held at Newlands Corner, Drove Road, Guildford, Surrey. Participants can choose between two distances: 10km and 15km. The event offers a scenic course starting from Newlands Corner, with parking available nearby.Runners can also opt for bundled en..

Dark Skies Surrey Hills is a night-time trail running event at Denbies Wine Estate in Dorking, set in the Surrey Hills. It offers a night-time 10-mile, 10K and 5K races, plus Canix events and 1K/2K kids’ races for 3–11 year-olds. The undulating, muddy courses wind through woodlands beneath the stars..

North Downs Way Ultra Run is a 30-mile guided trail from St Martha’s Hill, Guildford, Surrey, along and back along the North Downs Way, including the famous Box Hill. Organised by Running Adventures, the event is designed as an approachable introduction to ultra running, with the route cared for by..

Country to Capital Ultra is a 43-mile point-to-point ultramarathon from The Shoulder of Mutton Pub in Wendover to The Stowe Centre near London’s Little Venice. The route crosses the M25 by bridge and follows the Grand Union Canal towpath into London, finishing near Paddington. The course comprises a..

The Northampton 10K is a well-organized running event held at Northampton Racecourse Park, featuring a 2.2 km start followed by three laps around the racecourse. The course is accurately measured and takes place on pathway terrain, offering water stations and first aid support. Participants receive..

The Hankley Common 10km is a guided trail run located at Hankley Common Lower Car Park in Elstead, Surrey. This scenic 10km route offers runners the chance to explore beautiful trails rich in wildlife and historical interest, including the Atlantic Wall replica used for D-Day training. The course fe..

The Dirty Devil Stampede is a challenging and muddy running event held at the Bovington Tank Range in Bovington Lane. Participants can choose from 5k, 10k, or 15k distances, with a special Dark 10k race taking place at dusk on a different course. The race takes place on an army training ground, offe..

Arundel & SDW Winter Trails 2026 is a double gold-rated trail event along the South Downs, finishing in Arundel. Runners choose between a marathon along the South Downs Way from Heyshott to Arundel (featuring river runs, rolling fields, and a Gurkha Suspension bridge) and a 15-mile option that detou..

The Crocodile Challenge is a 6-hour running event held at Ryton Pools Country Park near Coventry in Warwickshire. The course is a runnable, relatively flat 3.3-mile loop around pools and open pasture with crushed stone paths and some minor rises. Participants can complete as many laps as they wish w..