An ultra marathon is defined as any running event longer than a traditional 26.2 mile (42.2km) marathon. Apart from that, pretty much anything else goes.
No, really. Aside from the lower limit of its length, there’s no upper limit on the distance, there are no rules on types of terrains, and there are rarely any restrictions in terms of unpredictable weather conditions. This inevitably means that you’ll be in for one of the most unique and taxing challenges of your life, as well as one of the most rewarding.
Running these huge distances also means that you can take in an extremely varied amount of scenery and terrain all in one go. From spiky mountain ridges and snow-topped hills to smouldering valleys and active volcanoes; they’re a great way to get to know a country’s (or countries in the case of the UTMB) landscapes whilst also pushing your mind and your body to its very limits.
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After plenty of discussion amongst the Outdoors Magic team (including our editor Will who ran across every mountain in Wales all in one go), we’ve agreed on our list of just some of the best ultra marathons around the globe at the moment…
Note: some of the marathon dates may have changed since the publishing of this article.
The Best Ultra Marathons Around the World
Likened more to a life-changing journey than just a race, here’s our favourite ultra marathons in no particular order…
- Ultra Trail du Mont Blanc, The Alps
- Dragon’s Back, Wales
- 13 Valleys Ultra, England
- Comrades Marathon, South Africa
- Western States 100, California, USA
- Spartathlon, Greece
- Marathon des Sables, Morocco
- Ultra X 125, Scotland
- Fire & Ice Ultra, Iceland
- Tarawera Ultramarathon, New Zealand
- Montane Lapland Arctic Ultra, Sweden
Ultra Trail du Mont Blanc, The Alps

Location: France, Italy & Switzerland
Distance: 110 miles (170km) +
Date: 26th to 31st August
As one of the most popular hiking trails in Europe, the Tour du Mont Blanc is a bit of a staple on the hiker’s bucket list. Come August, however, the route is home to the Ultra-Trail du Mont Blanc and becomes an ultra running hotspot, attracting keen runners from all over the world.
Though there are various races throughout this week-long festival, the heart of the event revolves around the 110+ mile race that loops around Mont Blanc, crossing France, Italy and Switzerland along the way. The terrain itself involves crossing rivers, alpine villages and forests, all with the Alps as a breathtaking backdrop.
Most people finish the race in 32 to 46 hours, though the best of the best run through the night and tend to finish in 20 hours. With 10,000m of climbing, it’s no surprise that only 60% of participants finish each year. It’s also worth noting that earning a place on the UTMB is very competitive and you’ll need qualifying points from other trail races to enter the ballot.
Dragon’s Back Race, Wales

Location: Welsh Mountains
Distance: 236 miles (380km)
Date: 1st to 6th September
The Dragon’s Back Race takes place along the mountainous spine of Wales, crossing both the Brecon Beacons and Snowdonia National Parks on the way. With 57,087 ft (17,400m) of height gain, the ascent actually adds up to two times the height of Everest.
Most runners average 63km per day – that’s 1.5x marathons a day – and finish over the course of six days. Tented accommodation is provided throughout, as well as food and drink.
Highlights include a scramble across Crib Goch, a full traverse of the Snowdon horseshoe, the glorious Cambrian mountains, including the remote summit of Drygarn Fawr, as well as Cardiff Castle at the finish line.
13 Valleys Ultra, England

Location: The Lake District
Distance: 115 miles (184.3km)
Date: 26th to 28th September
The 13 Valleys Ultra takes in some incredible scenery in the Lake District across approximately 115 miles (184.3km) of rugged terrain. You only have to look at the pictures to see what I mean.
Though 184.3km is the longest challenge and includes 13 valleys (hence the name), there’s actually four races to choose from in total. There’s the 2 Valleys (22km) if you fancy a shorter race, and then three ultra distances: the 5 Valleys (55km), the 7 Valleys (110km) and, of course, the 13 Valleys. The latter takes in 7000m+ of elevation and has a cut-off time of 46.5 hours.