Best Ultramarathons In The UK

Are marathons not quite long enough for you? Do you want to make them even more challenging by going off-road and over hilly terrain all around the UK? If so, here are some of the UK’s best long-distance trail races and ultramarathons, ranging from scenic 50km loops around the countryside to 24-hour events to very difficult races of 100 miles and more. Have you got what it takes? 

If you’re looking for other trail races, ranging from 5km to the marathon, then we’ve got a selection of some of the best trail races in the UK.

CENTURION RUNNING – NUMEROUS RACES
When: Throughout the year
Where: Throughout England
With 50km, 50 mile and 100 mile races, the Centurion events are for those who want to complete a trail ultramarathon. They have popular trail races on the North Downs Way, the South Downs Way (the South Downs Way 100 is one of the World Trail Majors), and around middle England, plus there’s the Thames Path 100 if you’d prefer a long run without the hills. Centurion are well-regarded for the quality of the courses, the event organisation, and the aid stations, but the events can sell-out very quickly. For those looking for something even longer, there’s the Winter Downs 200, a 200-mile loop connecting the North Downs and the south Downs, and it takes place in December – it’s one of the hardest races in the UK.  

ARC OF ATTRITION
When: 24-26 January
Where: Coverack
With races of 40km (25 miles), 80km (50 miles) and 160km (100 miles) around the rugged South West coast path in Cornwall, this can be a brutal beast of a race in wild January conditions, but that’s what attracts its many fans each year who take on the weather as much as the terrain. This is a race for serious trail runners with good experience over technical conditions.

MANCHESTER TO LIVERPOOL ULTRA 50
When: 18 April 2025
Where: Manchester
This is a flat (and fast, if you’re up for it!) ultra following the Trans-Pennine Trail, the Manchester Ship Canal and the River Mersey. It’s a very popular race and sells out quickly. It’s organised by GB Ultras who also have a 57-mile run from Glasgow to Edinburgh. 

ULTRA-X SCOTLAND
When: 3-4 May 2025
Where: Inverness
The main race is a two-day 110km stage race beginning in Inverness and running parallel to Loch Ness. The first day covers 60km and ends at a campsite for the evening, then begins again on day two where 50km runners join the action. It’s a great choice for those looking to cover a long distance but who want to break it up over two days. They also hold a similar format in the Peak District and Snowdonia, plus other runs around the world, including Rwanda, the Azores and Slovenia. 

UTMB SNOWDONIA
When: TBC May 2025
Where: Snowdonia, Wales
If you want to know what this race is like then they describe it as: ‘Beautiful beyond belief, savage beyond reason.’ This is a very difficult race around Snowdonia, with 25km, 50km, 50 mile and 100 mile races. It’s a great one for those looking to collect their stones for the main UTMB race, or wanting to take on one of the UK’s most spectacular and most-challenging ultras.

THE LAP
When: May and September
Where: Lake Windermere
Fancy running a 47-mile around Lake Windermere? If so, this is the race for you! You’ve got 24 hours to complete the loop around England’s largest lake and you have two choices: clockwise in May and anti-clockwise in September. It has five aid stations (including one where you can collect a drop bag), it’s open to both runners and walkers, the course is mostly on ungroomed trails, and the 2,500m of elevation gain gives a good mix of ups, downs and flats. It’s a good run for all levels. 

UK ULTRA SOUTH DOWNS 50KM
When: 25 May 2025 
Where: Falmer
With options to run a half marathon, 20 miles, 50km, 100km or 100 miles over the weekend, there’s plenty of choice for this very well-organised race which takes place over the South Downs and ends by the sea in Eastbourne. The routes are a mix of challenging hills and runnable trails, and always with great views. The aid stations have a great selection of food and drink. UK Ultra also organise several other ultra-distance races throughout the year. 

RAT RACE EVENTS – THE WALL
When: 14 June 2025
Where: Carlisle
Some of the more challenging and diverse trail running events in the UK and beyond are organised by Rat Race, including single day events and multi-day ultras. There are Sea To Summit ultra runs up the highest peaks in Scotland, England and Wales, and there’s the iconic The Wall (next run 14 June 2025), which follows the 70-mile length of Hadrian’s Wall from Carlisle Castle to Gateshead Baltic Quay, and it has a 26-hour cut-off time. If you want to have a peek at the route, then we followed a team of runners as they relayed along the route. 

ENDURE24 – READING & LEEDS
When: June 
Where: Reading and Leeds
How far can you run in 24 hours? That’s what Endure24 challenges you to do. Starting at midday, runners follow an 8km loop and attempt to run as far as they want to within 24 hours. You can sign up as a pair or team, or take it on solo. There’s a great atmosphere around the camp and the course. There are two events, one in Reading and the other in Leeds. 

James, Mo, Sarah and Tom took on the race in 2024 to see how far they could go!

RACE TO THE KING & RACE TO THE STONES
When: June & July
Where: Near Chichester (King), and Lewknor, Oxfordshire (Stones)
Organised by Threshold Trail Series, these are very popular trail races where both have a 50km and 100km option. Race To The King’s 100km course is two separate 50km loops, the first the flatter Coastal loop, then the hillier Castle loop along the South Downs ridge, and beginning and ending outside of Chichester. Race To The Stones follows the oldest path in Britain, and the undulating course cuts through the British countryside on the way to a finish in Avebury. The races are committed to Ultra50:50, which hoes for gender parity between its racers. 

THE SERPENT TRAIL
When: TBC July 2025
Where: Haslemere
The 100km route runs the full length of the Serpent Trail, with a 50km running half the trail and two shorter options with a 20km and 10km run. The full 100km snakes from Haslemere to Petersfield, via the highest point in the South Downs National Park at Blackdown, and a lot of woodland. You can have support crews and a pacer from halfway, if you’d like one. The whole event is exactly what you need from an ultra: well-marked, well-organised, and great aid stations. It’s part of the Freedom Racing series of runs, which are all worth checking out.

LAKES IN A DAY
When: 12 October 2024
Where: Caldbeck
This 50 mile race takes in the very top of the Lake District and also runs along the shore of Lake Windermere, giving you a full highlights reel of the Lakes as you travel from Caldbeck to Cartmel. It’s a difficult route with 4,000m of elevation and to keep you going there are three aid stations with hot and cold food. This is one for more experienced runners given the terrain and the distance. 

Lead image from UTMB Snowdon