The 6 Hardest Marathons In The USA: Get Ready For A Challenge

Although there is no way to create a definitive list of the toughest marathons in the US, we have put together a list of some of the most challenging marathons in the United States based on the difficulty of the course, the weather conditions, and other factors that can make a standard 26.2-mile marathon all the more challenging.

Ready for the ultimate test of your physical and mental fortitude and fitness? Keep reading for our list of the hardest marathons in the US.

We will cover: 

• What Makes a Marathon One of the Hardest Marathons In the USA?

• Here Are The 6 Hardest Marathon In The USA

Let’s dive in! 

What Makes a Marathon One of the Hardest Marathons In the USA?

Every marathon is inherently difficult because simply covering 26.2 miles on foot is quite a feat of physical and mental endurance.

So, what makes one marathon harder than another? What did we consider when we were trying to pick the toughest marathons in the US?

The primary factors that can make a marathon particularly challenging are the terrain and the weather conditions.

When it comes to terrain, this can involve extreme gains in elevation over the course of the race, with significant and steep uphills or an overall relentless uphill course profile, even if gradual, with little to no flat or downhill for reprieve.

The marathon may also be held at altitude, as altitude running is inherently more challenging because of the relative lack of oxygen in the atmosphere.

Another serene consideration that can contribute to a race being one of the hardest marathons in the US is the running surface itself. 

Trail marathons that have very technical terrain with lots of rocks and roots or sharp turns with deep overhangs are a lot more challenging than running a road marathon or trail marathon with a smooth and predictable running surface.

Some of the hardest marathons in the US earned that superlative due to the chance of extreme weather, such as high winds, freezing temperatures, sleet or snow, or oppressive heat and humidity.

For example, the Badwater Ultramarathon is notoriously difficult not just because it is an ultramarathon with an extreme distance but because the race is held in Death Valley, where the temperatures can get well over 115°F.

Having to navigate big swings in temperature can also make a marathon exceptionally hard, and this can occur particularly in cases where there are significant changes in altitude over the marathon race course.

Here Are The 6 Hardest Marathon In The USA

So, what are the hardest marathons in the US? Here are some of our picks for the toughest marathons in the USA:

#1: Pikes Peak Marathon

Almost every list of the hardest marathons in the US includes the Pikes Peak Marathon. Held in Colorado at the famous Pikes Peak mountain, this notoriously difficult marathon requires nearly 8000 feet of vertical gain over the 26.2 mile course. 

It is a trail marathon, and the terrain is rugged, with a narrow and winding path peppered with gravel, rock, sharp turns, and steep hills.

In 2022, the average finish time was 7:26:45, with the male winner clocking in at 3:40:41 and the female winner not crossing the finish line until 4:37:31.

According to a very detailed analysis carried out by RunRepeat in 2019, the average marathon finish time across all age groups, genders, and countries of origin in 2018 was 4:29:53. Among runners in the United States, the average marathon finish time for men was 4:31 and the average marathon finish time for women was 4:57. 

Therefore, the average finish time at the Pikes Peak Marathon of 7:26:45 is nearly three hours slower than the average marathon finish time worldwide, and the winners were not all that much faster than the average finish time for men and women US runners.

Ultimately, the Pikes Peak Marathon is usually considered to be the single hardest marathon in the US. 

In fact, in order to demonstrate that you have a sufficient level of fitness, you must run a qualifying event before you are allowed to register for the Pikes Peak Marathon.

This super challenging marathon course reaches a top elevation of a whopping 14,115 feet, so if you are not a Colorado native or do not live at altitude, you will certainly want to do a little bit of altitude training, or you might be really feeling the effects of altitude during the marathon.

You will gain just under 8000 feet over a distance of only 13.3 miles. 

Essentially the course is entirely uphill on the way there, and then you turn around at the summit to come back down.

Plus, the last three miles toward the summit are all above the tree line, and you have to do some amount of rock scrambling to ascend the trail.

The trail up the mountain has an average of an 11% incline grade, and the terrain itself is difficult, with lots of gravel, loose rocks, and dirt. The trail is also narrow and winding, which makes it difficult to run fast and pass other people.

Most runners find that just reaching the halfway point, or the summit of the mountain takes longer than the average finish time for most marathons.

It typically takes about 8 to 10 hours for the average marathoner to finish the race, which is over twice as long as the average marathon finish time.

Even the course record is notably slow. It was set in 1993 by Matt Carpenter and still stands at 3:16:39.

One really cool thing about the Pikes Peak Marathon, in addition to its accolade as being the hardest marathon in the US (which is undeniably a badge of honor for any successful finisher!), is the fact that it was the first marathon in the US to officially allow women to enter the race.

#2: Blue Ridge Marathon

The reason that the Blue Ridge Marathon is one of the toughest marathons in the US is that it has the most elevation change of any road race in the United States.

Over the 26.2 miles, you will have a total elevation gain and loss of nearly 7500 feet.

There is one particular section where you are ascending Roanoke Mountain, climbing 780 feet in just 2 miles with multiple switchbacks over the marathon course.

The Blue Ridge Marathon does have a total cut-off time of 7.5 hours, and there is a cut-off time at mile 22 of six hours. This means that if you have not passed the 22-mile mark after six hours since the race began, you are asked to exit the course and cannot complete the race, and your finish will not count.

#3: Red Rock Canyon Marathon

Although the Red Rock Canyon Marathon course outside Las Vegas is undeniably scenic, it is certainly challenging and not the marathon where you will likely set a PR.

The marathon course starts at an elevation of about 3800 feet. Runners gradually climb over the first 8.5 miles to the summit overlook at 4,771 feet.

The course then descends back to roughly the same starting elevation before climbing back up to the summit overlook at mile 18.5. 

The constant up-and-down of this rolling marathon course makes it quite demanding, so if you are looking for a fast time, this probably isn’t the marathon for you. 

However, if you would like to soak in the beauty of natural red rocks, you will be stunned by the scenery.

#4: Black Mountain Marathon

Any marathon with the word “mountain” in the course is likely to be difficult, and the Black Mountain Marathon in Black Mountain, North Carolina, is no exception.

This is one of the most difficult marathons in the USA due to the technical nature of the rugged mountain terrain and trails themselves, as well as the potentially life-threatening weather conditions that runners may face on race day, including blizzards.

Even the website for the Black Mountain Marathon warns runners of the rigors they are signing up for, cautioning the following: “DO NOT UNDERESTIMATE THE DANGERS OR THE DIFFICULTIES INHERENT IN THIS EVENT!”

#5: Grandfather Mountain Marathon

The Grandfather Mountain Marathon is often touted to be one of “America’s Toughest Marathons.”

This mountainous, scenic marathon takes place in the mountains of Boone, North Carolina.

There is a tremendous amount of elevation gain, and the trail is pretty tough in its own right, but there is fantastic crowd support, and the stunning scenery can make it totally worth the effort.

#6: Equinox Trail Marathon

Located in Fairbanks, Alaska, the Equinox Trail Marathon is one of the most challenging marathons in the US due to the difficulty of the trail and the steep climb up the Ester Dome.

In fact, runners ascend this Alaskan peak twice over the course of the marathon, with a total net elevation gain of 3300 feet.

Don’t forget that every marathon is inherently challenging. Running 26.2 miles is physically and mentally demanding and is an accomplishment even on the flattest and fastest marathon courses.

However, if you are truly a brave and intrepid soul looking to test your abilities to the max, consider taking on one of our picks for the hardest marathon in the US.

If you are looking for a training plan to get you there safe and sound, check out our marathon training plan database with plans for all timeframes and ability levels.