Trail Running calendar near Harwell 2025-2026

The Maverick Original Oxfordshire is a trail running event held at the historic Stonor Park estate near Henley-on-Thames, Oxfordshire. Set within the Chilterns Area of Outstanding Natural Beauty, the race offers three challenging routes: 22 km (long), 12 km (middle), and 7 km (short), featuring elev..

The Riverside Marathon & Half Marathon, organized by Phoenix Running, takes place in Walton on Thames, Surrey, along the scenic River Thames. The event features accurately measured and UK Athletics certified routes, with runners completing 4 laps for the half marathon or 8 laps for the full marathon..

The Surrey Hills Half Marathon is a scenic 13-mile guided trail run starting and finishing in Guildford, Surrey. The course showcases the natural beauty of the Surrey Hills, featuring landmarks such as St Martha's Church and hill, the village of Shere, and panoramic views from Newlands Corner and Ha..

The Sussex Downs Trail Run takes place in the scenic South Downs National Park, starting at Plumpton Racecourse near Lewes, UK. Offering three distances—22km, 12km, and 9km—the event caters to all abilities, including newcomers. The course features a mix of flat, tree-lined sections and challenging..

Endurancelife Dorset offers a challenging trail running event set along the stunning Jurassic Coast Path near Swanage. Participants can choose from four distances: 10K, half marathon, marathon, and ultra, with ascents ranging from 774 to 7,027 feet, making it a tough trail runner's paradise. The cou..

The Hurtwood 50K, organized by Freedom Racing, is a popular late-season ultra running event held in the scenic Surrey Hills. This 50-kilometer trail ultra features a fully signed long-distance route with additional race signage, ensuring clear navigation. The course includes an exciting out-and-back..

The Chasewater Christmas Pudding Dash is a festive running event held at Chasewater Country Park in Staffordshire. Offering 10k, 5k, and junior race options, the course features mostly flat, slightly undulating compacted trails around the scenic Chasewater Reservoir. The 10k race consists of two lap..

The ATW Grafham Water - Trail & Canicross is a scenic 10-mile trail running event set around the picturesque Grafham Water in Cambridgeshire. Participants will enjoy a route that begins on the iconic dam and winds through beautiful trails, including a Woodland Nature Reserve and Sanctuary Bay. The e..

The New Forest Xmas Trails is a festive trail running event hosted by BigFeat Events, set in the picturesque New Forest National Park. Participants can choose from four distances: 15K, 30K, Marathon, and 50K, all on challenging yet runnable off-road courses. The event begins at Holmesly Campsite, of..

The Mince Pie 10 is a festive 10-mile race held in Peacehaven, East Sussex, organized by Seaford Striders. The multi-terrain course features approximately six miles of farm tracks and bridleways, with the remaining four miles on quiet roads, including a challenging hill around mile six. Participants..

The Winter Downs 200 is a challenging 200-mile continuous trail ultramarathon held in South East England, forming a large loop through iconic trails including the North Downs Way, Vanguard Way, South Downs Way, Wayfarers Walk, and St Swithuns Way. Starting and finishing at Juniper Hall near Box Hill..

The Mince Pi Run - Races of 2 Decimal Places is a unique running event held at Shalford Park, Guildford, featuring distances from 3.14 to 31.4 miles, corresponding to 1 to 10 laps of a scenic, mostly flat off-road course with a few hills. There is also a Pi marathon option and a 1-mile fun run shape..

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 Slow and Dirty is a festive 19-kilometer trail race held in Sturminster Newton, Dorset, following a level, hard-surfaced route along a former railway line known historically as the Somerset and Dorset or "Slow and Dirty." The course offers scenic views along the River Stour valley, passing resto..

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, featuring a hilly and potentially snowy course that is scenic yet desolate and windy. The event supports The Royal British Legion Poppy Appeal and offers prizes across various age categories for both male and female ru..

The Knacker Cracker is renowned as "Britain's toughest 10k," featuring a challenging course that includes significant elevation changes, with a total ascent of 473 meters. The race, set in the scenic surroundings of Box Hill and Denbies Vineyard, offers a unique experience for runners, including a k..

Dark Skies Surrey Hills is an exhilarating night trail running event set in the picturesque Surrey Hills, featuring races of 10 miles, 10K, 5K, as well as Canix and children's races for ages 3-11. Participants navigate through enchanting woodlands under the stars, illuminated by headlamps, making fo..

The Country to Capital Ultra Marathon is a renowned 43-mile point-to-point race starting at the Shoulder of Mutton Pub in Wendover and finishing near Little Venice Canal Basin in London. Serving as the official opener to the ultra running season, it attracts a global field of elite and amateur runne..