Trail Running calendar near Harwell 2025-2026

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..

The Fitstuff G3 Series No.1 is a trail running event held at Newlands Corner, Drove Road, Guildford, Surrey. Participants can choose between 10km and 15km distances, with options to enter single races or bundled series of three runs. The event offers a scenic trail running experience in the Surrey c..

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 South Downs & Arundel Winter Trails is a trail running event held in the scenic South Downs area near Arundel. It offers challenging courses on rural, often single-track trails that traverse farmland and natural landscapes. Participants can choose between a 15-mile route and a full marathon dist..

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..

The Ashdown Forest 10 & 5 Mile Series is an eco-friendly trail running event held at Pippingford Park Manor in East Sussex. This series features two races—10 miles and 5 miles—across undulating, multi-terrain park and forest trails that showcase picturesque scenery. Designed to offer a guilt-free, s..

The Windsor Trail Run January 2026, organized by RunThrough UK, takes place at Alexandra Gardens in Windsor, UK. Set against the scenic backdrop of Windsor Castle, this event offers a flat, chip-timed trail course with two distance options: a 10K and a Half Marathon. Both routes feature well-marked..

The Stonehenge Stomp is a popular walking and running event organized by the City of Salisbury Athletics & Running Club, held near the iconic Stonehenge site. Participants can choose from fully marked trail distances of 5 km (family-friendly), 10 km, 20 km, 30 km, or 40 km, all offering scenic views..

The Moors Valley Wildwood Trail Series Half Marathon & 10K is a trail running event held at Moors Valley Country Park & Forest in Dorset. Scheduled for January 25, 2026, it offers two distances: a half marathon consisting of two laps and a 10K with one lap. The course features scenic woodland trails..

The Fitstuff G3 Series No.2 is a running event held at Hound House Road, Surrey GU5 9JG. Participants can choose between 10km and 15km race distances. The start line and parking are conveniently located in a field off Hound House Road, marked by flags and signs for easy navigation.The event offers b..

The Squirrel Challenge is a 6-hour running event held at Daventry Country Park, United Kingdom. Participants run or walk as many 3.3-mile laps as they wish within the time limit, making distances flexible from just over 5K to over 80K. The course features mostly crushed stone paths through tranquil..

The Westonbirt Arboretum Winter Night Race is an exciting running event set in the stunning National Arboretum, featuring over 2,500 tree species. Participants can choose between 5km and 10km routes, which showcase the arboretum's diverse landscapes and solid terrain, providing a unique blend of tra..

The Pilgrim Challenge is a renowned ultra marathon held along the historic North Downs Way in the UK, offering participants the choice to run or walk either 33 miles in one day or 66 miles over two days. The course features stunning landscapes, picturesque villages, and areas of outstanding natural..

The Hibernal Hills 50 Miles is a season-opening ultra running event held at Queen Elizabeth Country Park in Hampshire. This single-loop race covers 50 miles of predominantly trail terrain with approximately 6,400 feet of elevation gain, featuring runnable but undulating paths with some significant h..

The Westonbirt Arboretum Winter Day Race is a scenic running event set in the stunning National Arboretum, featuring over 2,500 tree species. Participants can choose between a 5km or 10km race, with routes that showcase the beauty and diversity of the arboretum's landscape. The event is designed to..

XTERRA Matterley is an off-road sporting event held at the scenic Matterley Basin in Hampshire, United Kingdom. Scheduled for February 14-15, 2026, it offers a variety of race formats including duathlons and trail runs suitable for athletes of all levels. The duathlon races feature distances such as..