Guide to UK’s 10 Hardest Running Trails
If you’re looking for a challenge, there are plenty of tough trails in the UK. From remote wilderness to windswept cliffs, these routes are more than trails – they’re tests of strengths, endurance and determination for any runner.
These ten tough trail running routes offer something for everyone, whether you’re looking for a fun day out with your running buddies or want to test yourself with a multi-day run. Whichever route you choose, we’ll help you to prepare with the right trail running gear to ensure you can cruise across rocks, roots, and rolling terrain.
We’ve worked out how tough each of the routes are by taking various factors into account, including the terrain, the elevation gain, prevailing weather conditions and distance.
So, let’s get right to it – here’s our guide to the ten toughest trails in the UK!
2. Skye Trail - Isle of Skye, Scotland
3. Scafell Sky Race - Lake District
4. Cape Wrath Trail - Scottish Highlands
5. Spine (Pennine Way) - Pennines
6. Hell of a Hill - Lancashire
7. Culver Cliff Wood & Dunkery Beacon Circular - Somerset
8. Cybi Coastal Trail Route - Wales
1. Dragon’s Back - Wales
Stretching across the spine of Wales, the Dragon’s Back route covers 236 miles across the country’s most mountainous regions. Expect an elevation gain of 17000m along the route, almost double the height of Mount Everest.
What makes this trail particularly challenging isn’t just the distance covered, but its unmarked and remote paths. If you’re up for the challenge – whether that’s tackling the full Dragon’s Back route over several days or choosing a shorter section – you’ll need to hone your navigational skills. For those who want to truly push their limits, the Dragon’s Back Race will be right up your street, tackling the full route over six days of challenging running.
2. Skye Trail – Isle of Skye, Scotland
Travel to Scotland’s mystical Isle of Skye to discover the Skye Trail, the perfect choice if you’re looking for a challenging adventure in a beautiful location. The unmarked route traverses 80 miles across the island, from Rubha Hunish (the most northerly point on Skye) to Broadford in the south. Along the way, you’ll run the dramatic Trotternish Ridge and in the shadows of the mighty Cuillin mountains.
You’ll need excellent navigation skills as this route isn’t for the faint hearted, with difficult terrain and potentially wet, windy weather. The route can easily be broken down into sections for shorter runs – or if you’re up for it, there’s also the Skye Trail Ultra that tackles the full distance.
3. Scafell Sky Race - Lake District
The Lake District is one of the best trail running destinations in the UK, and the Scafell Sky Race offers the very best of this mountainous region: with 2800m of ascent over 24.8 miles, it’s a route to be reckoned with!
The circular route traverses over the Lakeland Fells, through the Lakeland Valleys to the summit of Scafell Pike, England’s highest mountain. Participants in this route tackle rugged terrain but also immerse themselves in the beauty and untamed wilderness of the Lake District.
Brooks Trail Runner Luke ran the race in 2023 and confirmed that there are some runnable parts, but the descents in particular are technical. But although it’s a tough race, it’s also a stunning one. He told us: “The Lakes are of course beautiful; I felt so lucky to be surrounded by green hills and blue skies, doing something I loved. It was also a super hot day and I remember being desperate for a drink and plunged my face into a tiny brook halfway through the race!”
4. Cape Wrath Trail – Scottish Highlands
Venturing through the wild but beautiful Scottish Highlands, the Cape Wrath Trail is completely unmarked and runs through some of the most remote locations in the UK, from Fort William to Cape Wrath, the most north-westerly point on the British mainland. The route stays relatively low and doesn’t climb any huge peaks, but don’t be fooled. With a mixture of trails and pathless terrain, as well as the wild location and unpredictable weather, serious navigation skills are required to tackle this trail.
As it’s not an official National Trail, it’s not market and therefore there are several variations on this route, so you can take the one that suits you most. The slightly easier option is taking the Great Glen Way out of Fort William heading north, while the harder (but more beautiful option) is to head west to Glenfinnan and onwards to the wilds of Knoydart, before going north. The former variation is around 200 miles, while the latter option is closer to 232 miles. There’s even a race that takes a 249 miles route over eight days.
- Get the gear: You’ll need a comfortable pair of shoes that can tackle any terrain on the Cape Wrath Trail – enter Brooks Cascadia trail running shoes, providing stability, soft cushioning, and protection from the elements.
5. Spine (Pennine Way) - Pennines
The Spine Trail spans a huge 267 miles across the entire Pennine Way. The full route stretches from Edale in Derbyshire to the Scottish Borders, crossing the Peak District, Yorkshire Dales, Northumberland National Park, Hadrian’s Wall and the Cheviots along the way.
There are several races along the Pennine Way, including the Summer Spine Race and the Winter Spine, known as “Britain’s most brutal” – and for good reason. The full trail has a elevation gain of 13000m, crossing hilly terrain and crossing remote landscapes. You can easily split the route up into smaller sections for multi-day adventures or shorter runs, either by doing out-and-back or point-to-point runs and making use of public transport and local taxi companies.
- Get the gear: The Catamount trail running shoe is made for long-distance trail running, allowing for top-speed adventure and responsiveness. The TrailTrack rubber outsole provides excellent traction for quick uphill and downhill twists and turns.
6. Hell of a Hill – Lancashire
Located in Lancashire, the Hell of a Hill Marathon Route offers a unique challenge for those looking to push themselves in a race environment. This established trail route is centred around the steep Rivington Pike, where there’s a challenge to run a marathon – 26.2 miles – a day for five consecutive days. As if that wasn’t enough of a challenge, runners also face an elevation gain of a whopping 5.6 miles – that’s the same as the height of Mount Everest!
- Get the gear: Tackling mountains calls for the hard-working Caldera collection. These shoes offer substantial cushioning to absorb impact on rocky trails, robust support for significant elevation gains, and a breathable upper to keep feet comfy as temperatures fluctuate throughout the day.
7. Culver Cliff Wood & Dunkery Beacon Circular - Somerset
Nestled between Dunkery Hill and Horner Wood, in Somerset’s Exmoor National Park, this 24 miles trail features steep climbs, vast moorlands, serene valleys, coastal stretches and river crossings – in other words, it’s got a little bit of everything, so you’re sure to enjoy this route no matter what type of terrain you prefer. Regarded as a tough UK trail, this route isn’t for beginners – unless you truly want to push yourself to the limit. Just make sure you’re wearing grippy shoes, are confident at navigating across open moorland, and are prepared with the right clothing and equipment for a full day on the trails.
- Get the gear: For rugged and remote terrain, the Cascadia GTX trail shoe for men and women goes the distance. With its durable construction, aggressive traction, and waterproof coverage, the Cascadia is perfect for both rocky paths and moors.
8. Cybi Coastal Trail Route – Wales
The full Isle of Anglesey Coastal Path is 131 miles, circumnavigating the island of Anglesey in northern Wales. If you don’t fancy the full distance, then the Cybi Coastal Marathon trail offers a great alternative. With everything from beaches to cliffs, this route is as tough as it is rewarding. This diverse route also includes climbing Holyhead Mountain’s 220-metre peak at the trail’s northern tip. With an elevation gain of 4000m, this is a route for trail runners looking to take on an epic challenge.
- Get the gear: The weather can change quickly on the coast. Be prepared for anything with lightweight, breathable High Point Waterproof Pants for women and men. With a packable design, they’re easy to stow away when you don’t need them – and ankle zips help you get them on quickly when the rain comes.
9. Bob Graham Round – Lake District
The Bob Graham Round is one of the most difficult long distance running routes in the UK. Named for Bob Graham, who ran 42 peaks in the Lake District within 24 hours, the challenge is to follow in his footsteps and do the same.
It’s a huge undertaking, covering 66 miles with 26,900 feet of ascent. Runners can either go in a clockwise or anti-clockwise direction, but they must start and finish their round at Moot Hall in Keswick.
If you’re seeking a huge adrenaline rush, the Bob Graham Round could be the long-distance challenge for you. As if the distance, elevation and time constraints weren’t enough, you’ll also have to deal with steep climbs, difficult navigation, pathless terrain – and often poor weather conditions, too. Of course, you don’t have to do the whole route, and you don’t have to do it in 24 hours either – you could simply choose a couple of peaks to tackle, or turn it into a multi-day run.
10. Jurassic Coast, Southwest Coast Path – Dorset & Devon
The South West Coast Path is England’s longest waymarked footpath, stretching for 630 miles from Minehead in Somerset to Poole Harbour in Devon. The whole route has gorgeous views but arguably the most beautiful section is along the Jurassic Coast, which runs from Orcombe Point near Exmouth to Old Harry Rocks near Swanage, East Dorset.
The Jurassic Coast section of the route offers 95 miles of cliffs, beaches and coastal views. The terrain is varied, from rolling chalk hills to towering cliffs, sandy shores, and plenty of undulating hills amounting to 5000 metres of elevation – meaning this outstandingly scenic route is more difficult than it might initially seem.
- Get the gear: The Divide collection for men and women provides the essential traction and stability needed for the Jurassic Coast’s varied surfaces, plus weather-resistant protection for surprise showers.
Choose your next challenge
Whether you’re an experienced runner looking to level up with a technical challenge, or are looking for an off-road adventure, these trails all promise an unforgettable experience. Some of the terrain is tough and the locations remote, so just make sure you’re well prepared with navigational aids, plenty of fuel, and the right gear to traverse any terrain and you’re sure to have an amazing adventure!