Trail Running calendar near Harwell 2025-2026

Inaugural BOWUM is a 30 mile circular trail in Monmouthshire linking Skenfrith, Grosmont and White Castle via the Three Castles Walk and Offas Dyke Path. Enjoy rolling hills, well stocked checkpoints and no time limit.

Join the Chasewater Easter Egg Challenge on 05/04/2026 for scenic undulating multi terrain runs around the reservoir, with distances from junior to 20k. Dress as an Easter character and enjoy a bespoke medal, free photos and prizes.

Run the Mortimer 10km in Berkshire on a scenic, mainly off road two lap route through woodlands, with a standard 10 km and a dog friendly canicross. Expect undulating trails, chip timing, medals and a lively village atmosphere.

Challenge yourself on an 8 mile undulating trail around Freshwater, climbing about 900 feet and passing iconic spots like Tennyson Down and Alum Bay. Limited to 175 entries on 6 April 2026, this rugged multi terrain route offers stunning co..

Tackle the Rose of the Shires Ultra, 54 mile circular challenge around Brixworth Country Park across trails, towpath and country roads. Enjoy countryside scenery, navigation sections, on course support and a finishers medal.

Run the spring trails at Cowdray Estate with 5 km, 10 km, 10 mile, junior races and canicross options. Scenic sandy heathland and mixed trail sections through wildlife rich commons deliver a rewarding, characterful day out.

Take on the iconic South Downs Way 50, a 50 mile trail race on 11 April 2026 from Worthing to Eastbourne. Expect 85 percent trail, 5700 ft of climbing, sweeping chalk ridge views and a finishing lap on the Eastbourne Sports Club track.

Run the Henley River Half Marathon, 10K or Junior Race at Temple Island Meadows and enjoy scenic, mixed terrain trails along the River Thames. Expect themed medals, free photos and a lively event village with food, drink and family fun.

Run the Rosebud Marathon, a scenic 26.2 mile leg of the Rose of the Shires Ultra across Northamptonshire with roughly 60% trail and 40% road. Enjoy varied terrain, aid stations and live GPS tracking to Brixworth Country Park.

Take on four iconic Centurion 50 mile challenges across 2026 with the 50 Mile Grand Slam package, starting with South Downs Way on 11 April. Secure your spot when entries open 26 April 2025 for a season of epic trails and camaraderie.

Tackle The Big Cheese, a 15 mile off road fell race across the Mendip Hills with over 2,000 feet of climbing. Enjoy a fully marked course, finishers medal and tea and cake to celebrate at the finish.

Tackle 28 miles along the traffic free Brampton Valley Way on 12 April 2026, choosing to start from Market Harborough or Northampton for a scenic out and back challenge. Expect quiet trails, two tunnels so bring a head torch, feed stations..

Run a scenic 10k trail loop through the Nene Valley countryside, over green fields, farm tracks and old railway lines. Fully marked with an aid station, this spring race is ideal for runners wanting a country escape.

Take on the Wild Horse 200 series and run 200 miles across unforgettable Welsh trails and mountains. Pick the South Wales route finishing at Worms Head in April 2026 or the Mid Wales loop starting and ending in Machynlleth in June 2026.

Discover the Spring Trail Series on the Serpent Trail in the South Downs at Cowdray estate on 18 April 2026. Choose from 12 km to 110 km and enjoy a fully marked, supported route through greensand hills, rivers, woodland and heath.

Take on an 18 mile guided trail run across the iconic Malvern Hills, summit the ridge and enjoy woodland trails with an experienced coach leading at a social pace. Tickets are currently sold out.

Discover the Windsor 50 Ultra Challenge, a looped Great Park and Thames Path event offering 10 km, 25 km and 50 km options with Castle views and support along the route. Walk, jog or run from Windsor Racecourse and enjoy a lively festival a..

Tackle the Chiltern Ridge Classic 50K on 18 April 2026 along a scenic 51K Ridgeway route via Ashridge, Ivinghoe Beacon and Whiteleaf Hill. Limited to 400 runners, this UTMB race delivers big views, full support and a true trail challenge.

Experience a weekend of mountain running and walking in the Black Mountains and the Forgotten Landscape near Abergavenny on 18 and 19 April 2026. Choose 50, 30 or new 20 mile routes with stunning climbs, historic trails and a canal finish.

Join the Grand National trail run in Findon Village with a 10 km main race, new 5 mile course, a 10 km canicross and a 2 km kids loop at Nepcote Green. This charity event features bespoke medals, free photos and a best dressed jockey prize.