The 15 Most Popular & Best Ultramarathons in the World

Matthew Huff, a running writer

In This Article

So you’ve run a marathon, what comes next? The answer might be laying on your couch and never running again. It might be signing up for another marathon. Or, for the even more bold and daring, it might be an ultramarathon. There’s no more difficult feat in long distance running than the ultramarathon. They take months, if not years, of training for the hours upon hours of running. They also require a mind and body that won’t shut down when the going gets tough. The ultramarathon is one of the most grueling endeavors an athlete can take on, certainly shouldn’t be taken lightly, and one must take careful consideration on selecting the best ultramarathons for their ability.

If you are, however, hoping to level up post-marathon, here are the answers to some of your basic questions as 15 races you might consider signing up for. 

If you’re not quite ready for an ultramarathon but have been daydreaming about running an other-worldly beautiful course in the Alps, Emerald Isle, or Sahara Desert, you might be looking for a running vacation.

Before heading out on any of these ultramarathons, you’ll need to upgrade your trail running gear.

15 best Ultramarathons in the world.

Frequently Asked Questions About Ultramarathons

What is an ultramarathon? The answer is pretty simple. An ultramarathon is any race that’s longer than a marathon or 26.2 miles. That means that a 26.2-mile-long race would count as an ultra and so would a 1,000-mile race. There’s no discrimination in the ultra. 

What is the distance of the race? Ultras vary greatly in length, but common distances are 50K, 100K, 30 miles, 50 miles, and 100 miles.

If a race spans multiple days it is classified a “stage race” and those can be much longer, although they aren’t run in one continuous period. 

What is the average length of an ultramarathon? As you can imagine, the longer the race, the fewer people who attempt it. That makes the most popular distance 50K which is only a few miles longer than a marathon. Determining the average length is more difficult. 

How many runners per race? The amount of ultrarunners who start each ultra with their mind on the finish varies greatly from race to race. Large races like the Comrades Marathon welcomes thousands of runners each year, while others are unsupported and are ran by just a small handful. 

What are the best ultra marathons for beginners? In general, it’s best to ease into ultramarathoning. Start with something relatively flat, relatively cool, and relatively short, like a 50K not in the mountains. Then you can level up to a longer, hotter course with high elevation gain later. 

What are the best ultramarathons in the world? Here are the most popular and best ultramarathons you should add to your bucket list.

Olympic Valley the site of Western States Endurance Run the most popular and best ultramarathon in the United States.

Western States Endurance Run

  • Location: Olympic Valley (previously Squaw Valley), CA to Auburn, California
  • Date: June 29-30, 2024
  • Distance: 100 miles
  • Terrain: Hilly trail run through the Sierra Nevada mountain range
  • Website: https://www.wser.org/ 

When it comes to ultra running, the Western States 100 is the creme de la creme. It’s basically what Boston is to marathon running, with the best trail runners coming from across America and around the globe to compete in it. The rugged trail race winds through the mountains of northern California and gives runners a 30-hour cutoff to complete the course. Ultras are difficult to qualify for by design (the race director doesn’t want amateurs getting lost or injured), but Western States is more difficult than most. You have to run a certain time in one of the qualifying races to even enter the lottery to run this 100-mile race. If Western States is on your bucket list, you better get training. One of the most popular and best ultramarathons in the United States.

The best ultramarathon in the world held on Mont Blanc between France, Italy, and Switzerland.

Ultra-Trail du Mont-Blanc (UTMB) – France, Italy, Europe

  • Location: France, Italy, and Switzerland
  • Date: August 30, 2024
  • Distance: 100 miles
  • Terrain: Hilly trail run through the Alps around Mont Blanc
  • Website: https://montblanc.utmb.world/races/UTMB 

Before the UTMB, there was the Tour du Mont Blanc, a walking trail that circled the base of the highest mountain in the Alps. It has since become one of the world’s largest and most difficult ultras in the world with over 2,500 starters each year to race through three countries in Europe. The grueling course has nearly 33,000 ft of elevation gain and takes most runners nearly two days to finish. In order to enter the race, you have to earn a “running stone” from one of UTMB’s qualifying races. The more stones you’ve collected, the better your odds in the lottery are. Widely considered to be one of the best ultramarathons in the world.

Related: Run in the Italian Dolomites 

The Sahara Desert in Morocco home to the Marathon des Sables, a 250 km ultramarathon.

Marathon des Sables – Morocco, Sahara Desert

When it comes to the world of ultras, the goal is to push yourself through as much hardship as possible. That’s why this six-day running race through the Sahara desert was created. The six-day stage race was dreamt up by a French concert promoter who, himself, traversed the Sahara. You don’t need to qualify for the Marathon des Sables, and as far as endurance runs go, it’s on the slower side, with many people walking. But don’t let it fool you, the weather conditions are brutal so even though you aren’t running a 100-miler every day, it might feel even harder. One of the best ultramarathons you can find in north Africa.

Related: The running tour through the Sahara Desert

Canyon Endurance Runs runner in Auburn California one of the best ultramarathons in California.
Photo: UTMB

Canyon Endurance Runs by UTMB

  • Location: Auburn, California
  • Date: April 26-27, 2024
  • Distance: 100 miles, 100 km, 50 km, 25 km
  • Terrain: Hilly trail run through the Sierra Nevada mountain range
  • Website: https://canyons.utmb.world/races/100M 

If you’re looking to run your first ultra or you want to run Western States but can’t quite qualify, then the Canyon Endurance Runs (which just so happen to earn you running stones) are a nice option. The race, which is run through the same area and even on some of the same trails as Western States, has a variety of lengths to choose from. And while you’re required to carry your own water, there are also aid stations on the course, which cannot be said for all these races. Our pick for the best ultramarathons produced by UTMB outside of Chamonix.

Hardrock 100 view of Silverton, Colorado.

Hardrock 100

  • Location: Silverton, Colorado
  • Date: July 12, 2024
  • Distance: 100 miles
  • Terrain: Trail run through the Rocky Mountains in remote Colorado
  • Website: https://hardrock100.com/ 

Hikers often attempt to traverse the fourteeners or mountains that are over 14,000 ft above sea level. The Hardrock 100 actually has you scaling one of those during a 100 mile ultra. Like other prestigious ultras, you must complete a qualifying race in order to enter the lottery for the Hardrock 100, but that’s with good reason. The website itself says, “mountaineering, wilderness survival and wilderness navigation skills are as important in this event as your endurance.” This is not your average footrace, it’s a survival challenge. 

Comrades Marathon
Comrades Marathon

Comrades Marathon

  • Location: Durban, South Africa to Pietermaritzburg, South Africa
  • Date: June 9, 2024
  • Distance: 90 km
  • Terrain: A road race known for its five hills
  • Website: https://www.comrades.com/ 

The Comrades Marathon is by all accounts the oldest and the largest ultra marathon. The race was founded in 1921 to commemorate soldiers who had died in World War I and has grown in the last 100+ years to accommodate 25,000 runners each year. That makes it one of the largest running races in the world, let alone in the ultra scene where races will cap at 100 participants. A fun fact about Comrades is that the course swaps the start and the finish every other year, so you really need to run the Comrades Marathon two years in a row if you want to get the full effect. One of the best ultramarathons with a massive group of runners!

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Spartathlon – Greece

  • Location: Athens, Greece to Sparti, Greece
  • Date: Fall 2024
  • Distance: 246 km
  • Terrain: Part road race/part mountainous trail run
  • Website: https://www.spartathlon.gr/en/home/ 

Those of you up on your running history will know that the modern marathon is based on an historical figure named Pheidippides, who supposedly ran from Marathon to Athens in order to proclaim the outcome of the Battle of Marathon. However, in conflicting accounts, Pheidippides actually bypassed Athens and ran all the way to Sparta. That is the basis for the modern Spartathlon which is run every year. You have to qualify by running another ultra and the race has 75 checkpoints where the cut off runners who aren’t fast enough. Hopefully you won’t die at the end like our boy Pheidippides supposedly did. One of the best ultramarathons that ties into the history of running.

Frozen Head State Park, Tennessee
Jacob Ian Wall, Flickr

Barkley Marathons

  • Location: Frozen Head State Park, Tennessee
  • Date: Spring 2024
  • Distance: ~ 100 miles
  • Terrain: No marked course through wooded mountains
  • Website: There isn’t one. 

The Barkley Marathons is perhaps the most bizarre running race in the world, let alone on this list. With only 35 entrants each year, the race sends runners on five 20ish mile loops off-trail in the backwoods of Tennessee. Each loop requires runners to find book markers where they must rip out pages corresponding to their bib numbers. The difficult navigation, intense terrain and 100-mile course make it near impossible to finish with only 17 runners ever completing the course before its 60 hour cutoff. One of the best ultramarathons that’s more of an adventure race for very resilient runners. 

Badwater 135, one of the best ultramarathons for extreme runners, traverses Death Valley in the summer.

Badwater 135

  • Location: Death Valley, California to Mt. Whitney, California
  • Date: July 22-24, 2024
  • Distance: 135 miles
  • Terrain: Trail run through a desert and three mountain ranges
  • Website: https://www.badwater.com/event/badwater-135/ 

The Badwater 135 is described as the “the world’s toughest foot race” and if you’ve got this far in the article you know that in the world of trail running ultras, there are plenty of tough races. The Badwater, however, starts 282 feet below sea level in the excruciating heat of Death Valley (in the middle of July I might add) and then forces runners to run through two mountain ranges before climbing to the top of Mt. Whitney, 14,505 feet above sea level. It’s a grueling multi-day affair that even most ultramarathons wouldn’t dare attempt. 

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Leadville Trail 100

The Leadville Trail 100 is nicknamed “The Race Across the Sky” because of how high the course altitude is in comparison to most other races. Starting off in Leadville, Colorado, the race begins with runners at an altitude of 10,000+ feet, and the course, which traverses the Rocky Mountains, only goes up from there. Two especially daunting elements of Leadville are the out-and-back course meaning you have to run all the hardest parts of the course twice AND the staggeringly high altitude. You can’t really train for Leadville someplace like Florida. If you do, you’re gonna be in for a world of hurt. 

image 127
Patrick Lair | U.S. Forest Service, Southwestern Region, Kaibab National Forest

Grand-to-Grand – National Park, USA

  • Location: Arizona/Utah border
  • Date: September 22-28, 2024
  • Distance: 171 miles
  • Terrain: Remote trail race with disparate terrains that include desert and mountains.
  • Website: https://g2gultra.com/ 

This multi-day epic odyssey gets its name from the Grand Canyon and the Grand Staircase, two of the southwest’s most impressive geological formations. Runners will start at the Canyon and race to the Staircase on a seven-day stage race. While that does mean the 171 miles are broken up into stints, the hard part about Grand-to-Grand is that it’s unassisted and self-supported, meaning no aid stations and you have to carry whatever you need. In the remote desert of Arizona, you could end up needing quite a lot. 

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Transalpine Run – Switzerland

  • Location: Austria, Switzerland, and Italy
  • Date: September 7-13, 2024
  • Distance: 268 km
  • Terrain: Mountains. It’s the Alps after all
  • Website: https://transalpine-run.com/en/ 

If you said, “Hey, let’s take the UTMB and make it last a whole week,” you’d come up with the Transalpine Run, and as the name implies, it’s a run across the Alps. Most days you’re running something in between a half marathon and a full marathon but through one of the most intimidating mountain ranges in the world. The Transalpine Run, however, does give you the option of running it alone, as a pair, or as a team. While most ultras are individual efforts, the TAR gives you some variety. 

Related: Run through the Alpe-Adria mountain range.

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Lakeland Trails Ultra – London

  • Location: Lake District, United Kingdom
  • Date: July 13, 2024
  • Distance: 100 km
  • Terrain: Hilly trail run with a few mountains to climb
  • Website: https://www.lakelandtrails.org/ultra 

Sorry to London, but the UK’s Lake District in the northern section of England is one of the most beautiful sections of the country. There are mountains, but also plenty of beautiful valleys, forests, and, well duh, lakes. This 100K race is certainly challenging in its own right, but compared to the other races on this list, is in a much kinder climate and terrain. Plus with plenty of freshwater lakes along the course, it you get a little too hot, you can always pop off for a swim. 

Tarawera Ultramarathon - New Zealand
Tarawera Ultramarathon

Tarawera Ultramarathon – New Zealand

  • Location: Rotorua, New Zealand
  • Date: February 17-18, 2024
  • Distance: 100 miles
  • Terrain: Hilly trail run past lakes, beaches and through tropical forests
  • Website: https://www.taraweraultra.co.nz/ 

Like the Canyon Endurance Races, New Zealand’s premiere ultra is also organized by UTMB and awards runners some of those coveted “running stones.” While many of the races on this list have been run in either desert or mountain climates, the Tarawera Ultra is a tropical affair. You’ll run through lush foliage and beside crystal water, as you check off the miles. Also like the Canyon Endurance Races, Tarawera provides runners with a number of distances to choose from. The 100 miler is the classic length, but 102 km, 50 km, and 21 km options are also available. 

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Moab 240

The Moab 240 is a multi-day race but unlike other multi-day ultras that work as stage races with set start and ending points for each day, the Moab 240 allows runners to go at their own pace provided they finish in the designated 116 hours. There are four sleep stations and 15 aid stations, but runners determine their own speed, schedule, and how long to sleep for. The ultra runs through the beautiful desert countryside near Canyonlands and Arches National Parks and so is popular. Enter the lottery and keep your fingers crossed that you get chosen.

Recap of the best ultramarathons

If you plan to run an ultramarathon, you’ll want to invest more heavily into training and nutrition than you have for any other of your race distances. Consider a training app like Runna or one that specializes in trail running like Vert.

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