My Thoughts: The 10 Best Ultramarathons and Trail Races in the World (2027)

1. Ultra-Trail du Mont-Blanc UTMB

The Ultra-Trail du Mont-Blanc (UTMB) ranks first as the best overall ultramarathon due to its unrivaled prestige, stunning Alpine scenery, and world-class field. The 171 km loop around Mont Blanc traverses France, Italy, and Switzerland, accumulating 10,000 meters of climbing, with most finishers taking 30 to 46 hours. The entry fee is near €350, and winning times for elite men and women sit around 19 to 20 hours.

UTMB is for runners seeking the ultimate challenge and global recognition, not for those on a tight budget or with limited qualifying points. It trades away accessibility for prestige, requiring a points-and-lottery system that makes a bib the sport's biggest prize. Compared to the Western States 100, UTMB offers more vertical gain and a more international, festive atmosphere, but it is significantly harder to enter.

2. Western States 100

The Western States 100 ranks second as the world's oldest 100-mile trail race, offering a historic and brutally hot challenge through California's Sierra Nevada. Run from Olympic Valley to Auburn every June, the course features iconic river crossings and canyon climbs, with June heat often topping 38°C. The entry fee is about $525, and the lottery is famously hard, with an acceptance rate under 10%.

This race is for experienced ultrarunners seeking a classic, fast, and well-organized hundred-miler with deep American history. It trades away altitude and extreme vertical gain for speed and heat management, making it a different test than the Hardrock 100. Compared to UTMB, Western States is more accessible in distance profile but equally difficult to enter, with a lottery that demands patience.

3. Hardrock 100

The Hardrock 100 ranks third as arguably the hardest 100-mile race in North America, set in Colorado's San Juan Mountains with about 10,000 meters of climbing. The loop course averages an elevation above 3,350 meters, with a high point over Handies Peak at more than 4,260 meters, where thin air and scree fields test every runner. The entry fee is about $235, but lottery odds are among the worst in the sport.

This race is for elite mountain runners who thrive on technical, high-altitude terrain and want a pure, no-frills test of endurance. It trades away spectator access and fast times for solitude and raw wilderness, offering a stark contrast to the festive atmosphere of UTMB. Compared to Western States, Hardrock is slower, steeper, and more dangerous, demanding superior acclimatization and scrambling skills.

4. Tor des Géants

The Tor des Géants ranks fourth for its extraordinary 330 km single-stage mountain ultra in Italy's Aosta Valley, accumulating about 24,000 meters of climbing. This race is run continuously with a 150-hour cutoff, making it a week-long endurance epic that crosses high mountain passes and remote valleys. The entry fee is approximately €800–€900, and the field is limited to about 700 runners, preserving an intimate, adventurous spirit.

This race is for the most self-sufficient and mentally resilient ultrarunners who crave a multi-day, self-navigated adventure rather than a fast competition. It trades away speed and comfort for an immersive, transformative experience that few other races can match. Compared to the Hardrock 100, the Tor des Géants is vastly longer and more demanding, requiring exceptional logistical skills and sleep management.

5. Marathon des Sables

The Marathon des Sables ranks fifth as a legendary self-supported 250 km stage race across the Moroccan Sahara, run over about six days. Runners carry all their own food and gear, with entry fees around €3,000–€4,500 including logistics and support. The extreme desert heat, sand dunes, and long stages make it a unique test of survival and endurance, not just running ability. The race's iconic status and harsh conditions attract a diverse international field seeking a profound adventure.

This race is for adventurers who prioritize experience over speed and are willing to pay a premium for a fully organized, bucket-list expedition. It trades away the mountain scenery and technical terrain of races like UTMB for a brutal, self-reliant desert challenge. Compared to the Tor des Géants, the Marathon des Sables is shorter in total distance but equally demanding in terms of heat management and carrying capacity.

6. Leadville Trail 100

The Leadville Trail 100 ranks sixth as the best value among premier 100-mile races, offering a storied high-altitude course through Colorado's Rockies. The out-and-back route crosses Hope Pass and never drops below 9,200 feet, with a 30-hour cutoff and a famous big belt buckle for sub-25-hour finishers. The entry fee is about $315–$365, and its lottery is more attainable than Western States or Hardrock, making it a realistic goal for many runners.

This race is for runners seeking a prestigious, high-altitude hundred-miler without the astronomical entry costs or impossible lottery odds of other majors. It trades away the technical terrain of Hardrock for a more runnable but still demanding course, and it lacks the international spectacle of UTMB. Compared to the Marathon des Sables, Leadville is far more affordable and accessible, yet it still delivers a genuine test of endurance.

7. Comrades Marathon

The Comrades Marathon ranks seventh for its unique mass-participation road ultra in South Africa, covering 87–90 km between Durban and Pietermaritzburg. Run annually since 1921, the race alternates between 'up' and 'down' directions, with a strict 12-hour cutoff and roaring roadside crowds. The entry fee is around R1,200–R2,000 (roughly $65–$110), plus a qualifying marathon time, making it one of the most affordable top-tier ultras.

This race is for runners who thrive on crowd energy and prefer a fast, road-based challenge over technical mountain terrain. It trades away the wilderness solitude of races like the Tor des Géants for a vibrant, city-to-city celebration of running. Compared to the Leadville Trail 100, Comrades is longer but lower in altitude and vertical gain, offering a different kind of physical test.

8. Badwater 135

The Badwater 135 ranks eighth for its extreme, invitation-only 135-mile race from Death Valley's Badwater Basin to the Mount Whitney portal. The course starts at 86 meters below sea level and climbs to over 2,500 meters, with July heat that can top 49°C. The entry fee is about $1,500, and the race is limited to about 100 runners, requiring a proven track record in ultrarunning.

This race is for elite ultrarunners who have already conquered major hundreds and seek the ultimate challenge of extreme heat and desolation. It trades away scenic beauty and crowd support for a stark, punishing environment that demands meticulous planning and crew support. Compared to the Comrades Marathon, Badwater is far more exclusive, expensive, and dangerous, offering a completely different kind of endurance test.

9. Javelina Jundred

The Javelina Jundred ranks ninth as a friendly, looped 100-mile desert race in Arizona's McDowell Sonoran Preserve, perfect for first-time hundred-milers. The flat, fast course is a reliable Western States qualifier, with an entry fee of about $250–$300. The race features a festive, Halloween-themed atmosphere with costumed runners and aid stations, making it a fun and accessible introduction to the distance.

This race is for runners seeking a beginner-friendly, well-supported 100-mile event with a strong community vibe and high finish rates. It trades away the altitude and vertical gain of races like Leadville for a more forgiving, runnable course that suits a variety of paces. Compared to the Badwater 135, Javelina is far more affordable, less extreme, and much easier to enter, making it an ideal stepping stone.

10. Lavaredo Ultra Trail

The Lavaredo Ultra Trail ranks tenth as a hidden gem in Italy's Dolomites, offering a 120 km course with 5,800 meters of climbing. The race is set against the iconic jagged peaks of the Tre Cime di Lavaredo, with entry fees around €200–€250 and better lottery odds than UTMB. Aid stations serve real Italian espresso and fresh pasta, and the finish line in Cortina d'Ampezzo provides genuine local support.

This race is for runners who want a competitive, scenic, and less crowded alternative to UTMB, with a more intimate and authentic atmosphere. It trades away the global prestige and massive crowds of UTMB for a smaller, more personal experience in stunning Dolomite scenery. Compared to the Javelina Jundred, Lavaredo is far more technical and mountainous, demanding better climbing and descending skills.

How we ranked these

This ranking measured five weighted factors: prestige and historical significance (25%), course terrain and elevation gain (25%), atmosphere and community support (20%), accessibility of entry via lottery or qualification (15%), and overall value including entry fee and logistics (15%). Data was drawn from official race websites, ITRA classifications, and runner-reported experiences.

Each race was scored on a 100-point scale, then weighted to produce a final ranking that prioritizes the complete race experience over any single metric.

This ranking deliberately ignored commercial sponsorship scale, social media popularity, and prize purse size. These factors often inflate a race's reputation without improving the runner's actual experience. A race like UTMB has massive commercial backing, but that doesn't make it better for a mid-pack runner than a smaller event like Lavaredo. The goal was to identify races that deliver exceptional personal challenge and memorable moments, not those that generate the most marketing buzz.

What to look for

When choosing between these races, the real differentiators are your personal strengths and preferences. If you thrive on crowds and global spectacle, UTMB is unmatched. If you want a high-altitude challenge with a more attainable lottery, Leadville offers the best value. For self-supported adventure, Marathon des Sables tests logistics as much as running. Consider your tolerance for altitude, technical terrain, and heat. A sea-level runner should avoid Hardrock without significant acclimatization.

Budget also matters: Badwater costs $1,500 plus travel, while Javelina is under $300.

The most common mistake is chasing prestige over fit. Runners enter UTMB or Western States because they're famous, then struggle with the lottery, travel costs, and course difficulty. Instead, match the race to your experience level and goals. A first-time 100-miler should start with Javelina's flat, fast loop, not Hardrock's 10,000 meters of climbing. Build your resume with accessible races, earn qualifying points, and then tackle the bucket-list events.

The best race is the one you can finish and enjoy, not the one with the most Instagram followers.

Related questions

What is the hardest 100-mile race in the world?

Hardrock 100 is widely considered the hardest 100-mile race in the world due to its extreme altitude, with an average elevation above 3,350 meters, and 10,000 meters of climbing. The thin air, technical scree fields, and unpredictable weather make it a brutal test. Only about 140 runners finish each year, and lottery odds are among the worst in ultrarunning.

How do I qualify for the UTMB lottery?

To enter the UTMB lottery, you must earn qualifying 'Running Stones' by completing UTMB World Series events. Each event awards stones based on distance and finish time. You also need a certain number of ITRA points from previous races. The lottery typically opens in December, and acceptance rates are around 15-20%. Plan two years ahead to accumulate enough stones.

What is the best first 100-mile race?

Javelina Jundred in Arizona is often recommended as the best first 100-mile race. It's a looped course on relatively flat, fast trails, with entry around $250-300 and no lottery. The desert climate is predictable, and the aid stations are well-stocked. It's also a Western States qualifier, making it a practical stepping stone to bigger races.

How much does it cost to run the Marathon des Sables?

The Marathon des Sables entry fee is roughly €3,000 to €4,500, which includes logistics, food, and support during the six-day, 250 km self-supported stage race across the Moroccan Sahara. This does not include flights, gear, or pre-race accommodation. It's one of the most expensive ultramarathons, but the experience is unique.

What is the difference between UTMB and CCC?

UTMB is the main 171 km race around Mont Blanc with 10,000 meters of climbing, while CCC is a 101 km race on similar trails but with less elevation gain, around 6,100 meters. CCC is often seen as a stepping stone to UTMB, with a less competitive lottery. Both start and finish in Chamonix, but CCC has a smaller field and a different atmosphere.

How do I train for high-altitude races like Leadville?

Training for high-altitude races requires gradual acclimatization. Arrive at altitude at least 10-14 days before the race to allow your body to produce more red blood cells. In training, focus on steep hill repeats and long back-to-back runs. Consider using an altitude tent or doing interval training at simulated altitude. Hydration and iron-rich foods are also crucial.

What is the Comrades Marathon?

The Comrades Marathon is an 87-90 km road ultra in South Africa, run between Durban and Pietermaritzburg, alternating direction each year. It's the world's oldest ultramarathon, dating back to 1921. Entry requires a qualifying marathon time and costs about $65-110. The race is famous for its massive roadside crowds and strict 12-hour cutoff.

What gear is mandatory for UTMB?

UTMB mandatory gear includes a hydration pack with at least 1 liter capacity, a headlamp with spare batteries, an emergency blanket, a whistle, a phone, food reserves, and a waterproof jacket. You also need warm layers, a hat, and gloves. The full list is on the official website and is strictly checked at registration. Expect to invest $500-1000 in quality gear.

FAQ

Are these races only for elite runners?

No, most have cutoffs generous enough for mid-pack runners. UTMB requires qualifying points and a lottery, but events like the Leadville Trail 100 have a lottery too, with a typical acceptance rate around 20-30%. Many 50 km races on the list have no lottery at all.

How much do these races typically cost to enter?

Entry fees vary widely, from about $150 for a 50 km event up to over $1,500 for multi-day stage races like the Marathon des Sables. UTMB is around €350, while Leadville is roughly $315-365. Most single-day 100 milers fall in the $200-500 range.

Do I need to qualify or win a lottery for every race?

No, but several require it. UTMB uses a points-and-lottery system, and Leadville also has a lottery. Others, like the Western States 100, have a competitive lottery with a typical acceptance rate under 10%. Many shorter or less famous races are first-come, first-served.

What's the hardest part of training for these races?

The biggest challenge is consistent vertical gain training. Most of these races have 5,000-10,000 meters of climbing, so you need to build hill endurance over months. Long back-to-back runs on terrain similar to the race course are essential, and many runners take 6-12 months to prepare.

Can I run these races if I live outside the host country?

Yes, most are international events with no residency restrictions. UTMB, for example, draws runners from over 100 countries. You may need to plan for travel, visas, and altitude acclimation, especially for high-altitude races like Leadville (starting at 10,000 feet).

What gear do I need for an ultramarathon?

Mandatory gear lists vary by race but typically include a headlamp, hydration system, emergency blanket, whistle, and weather-appropriate clothing. Some races require a specific pack or poles. Expect to invest $200-1,000 in gear, depending on conditions and personal preferences.

How do I choose between UTMB and Western States?

UTMB offers Alpine scenery and a global spectacle with 10,000 runners across distances, while Western States is the historic 100-mile race in California's Sierra Nevada with intense heat. If you prefer European charm and a bigger event, choose UTMB. If you want a classic American hundred with a lottery, choose Western States.

What is the Tor des Géants?

The Tor des Géants is a 330 km single-stage mountain ultra in Italy's Aosta Valley with 24,000 meters of climbing. Runners have 150 hours to finish, running continuously through the Alps. Entry costs about €800-900. It's an extreme endurance event that attracts a small, dedicated field.

How do I get into Badwater 135?

Badwater 135 is invitation-only. You must apply and demonstrate significant ultramarathon experience, including completing several 100-mile races. Entry costs about $1,500. The race runs 135 miles from Death Valley to Mount Whitney in July, with temperatures exceeding 49°C. It's one of the most brutal races on earth.

What is the best way to prepare for the mental challenges of a 100-miler?

Break the race into small segments, focusing on the next aid station rather than the finish. Embrace low points as normal and use a 'race script' with reminders. Find a pacer or run with others. Most importantly, have a personal 'why' that keeps you going when things get dark.

Sources

• https://itra.run/
• https://ultrarunning.com/
• https://worldathletics.org/
• https://www.runnersworld.com/
• https://www.trailrunnermag.com/
• https://trailrunner.com/
• https://www.atra.org/

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