Mammoth Cave Race Report: 50K/25K

This Mammoth Cave Race report will share what you need to know to run a fun but challenging 25K or 50K in Kentucky's only national park!

The Mammoth Cave 50K/25K trail race in western Kentucky is one of the few races held within the boundaries of a national park, and when I heard about it, I knew we had to check it out.

We signed up for the race in 2025. I opted for the 25K (my longest run yet) and my husband signed up to do (his second) 50K. Here’s how it went!

Where Is the Mammoth Cave Race Held?

The race begins and ends in Park City, Kentucky. The course is primarily within the bounds of Mammoth Cave National Park.

The race is an out-and-back route that starts and ends with a short (around a mile) section of road running, and then moves onto the gravel Mammoth Cave Rail Trail.

The 25K runners do the route once, and the 50K runners do the route twice.

Any turns or trail junctions were very clearly marked.

Interested in visiting the national park before or after you race through it? Check out our park guide, as well as other ideas for things to do in the area.

What Are the Trail Conditions?

This trail is beautiful to run on. It’s a well-maintained gravel path. When we were there, there weren’t any pot-holes or ruts in the trail.

How Hard Is This Trail?

The race director called this course “surprisingly difficult,” and I think for both of us that was true, but for different reasons. For me, it was the longest distance I’d ever run.

For those doing the 50K, there’s an added mental challenge when you come back to the start/finish area and have to leave and do the course all over again.

That said, while this course may be difficult compared to a very flat road race, we found the trail itself to be moderately easy (other than the distance).

There’s some elevation change, but it’s very minor compared to other trails we’ve done, like the Big Turtle 2.0 in eastern Kentucky. (The Mammoth Cave Race is only about 900 feet total in 16 miles.) Most of the elevation change is in two steeper sections of trail.

Do I Need Trekking Poles?

Probably not. This is a trail that feels much more similar to road running than to a technical trail run.

If you’re not sure if you’d need trekking poles, try to find a gravel road near you (such as a forestry road) and do some practice runs on it.

(I saw zero trekking poles while we were there.)

Aid Stations on the Mammoth Cave Race

When we did the race in 2025, there were three aid stations: one at the 4-mile mark, one at the 8-mile turn-around point, and one at the start/finish line (which also serves as the mid-point aid station for 50K runners).

Each aid station was well stocked. The year we were there, the 4-mile aid station had Scratch-mix water (an electrolyte carb blend), plain water, Coca-Cola, gels, snacks and a porta-potty. The 8-mile aid station had pickle juice, pickles, Scratch gummies and the same drink options.

At the start/finish aid station, there were physical therapy stations available to runners, as well as drink and snack options and flush toilets. I especially appreciated the warming station here since I was waiting around for 50K runners.

What Gear We Used

We each carried a running vest with two water bottles. (I used this vest; he used this one, with these water bottles.)

After doing some of my practice long runs on gravel roads, I opted to wear a shoe with more cushioning than my normal running shoes. I wore the Altra Timp trail runners.

He wore Altra Wilds for the first 25K and then switched to Altra Lone Peaks for his second half of the race. Here are more details on the Altra Lone Peaks.

The trail gaiters I wore probably weren’t necessarily, but they matched my outfit and kept my laces tied.

Even though we both wore trail runners, the trail was fairly tame and road shoes would’ve likely been fine.

Can I Have a Drop Bag?

The year we ran, 50K runners were allowed to have a drop bag that they left at the start/finish area. This allowed them to access any needed items in between race laps.

Participant and Time Limits

The number of race participants, as well as how long they have to complete the race, is limited by their National Park permit.

The year we raced, all runners had eight hours to complete the course. (That’s a very generous time limit for the 25K course and a fairly challenging time limit for the 50K.)

This race did sell out the year we ran it, so advance registration is a must.

Race Swag

We loved our race goodies! The bibs were cute, the finisher medals were adorable, and I absolutely love the ceramic mug!

Mammoth Cave Race: Overall Impressions

We found this to be one of the most well-run, enjoyable race experiences we’ve ever had.

The race director was highly responsive to any questions (via email or Facebook), and on race day he was around to help with questions. He even took the time to give directions to a friend of ours who was attempting to meet a runner at the 8-mile aid station to cheer her on.

When we signed up, I didn’t intend to do this race a second time, but it was such a great experience that I’d be thrilled to sign up again. If you’re considering registering, go for it!