Race cancelled due to damp course conditions and imminent threat of rain on race day. 

Opens 5/13 at 11am

Created by RJ Thompson of Native Endurance, MOZO DOUBLE UP is one of the toughest East Coast Mountain races around. Only 70 lucky souls will get the chance to take on the Double Up in 2021! This year Ironwood Adventure Works has partnered with RJ to bring back the Double Up after missing 2020.


Rugged and Unforgiving

This is not your average trail run.  You will be going up or down most of the time, with zero opportunity to lose your focus.  There are no-fall zones (meaning if you fall, serious injury or death may result), and quad-busting descents over some of the most technical terrain you can find.  If you don't run hills, don't consider this race.  If you do run hills, run more of them, and run them often.

Alpine Tundra

You will be traversing areas with high alpine vegetation. Please read more about this fragile ecosystem.

Course Description - Click here for map

The race begins at the base of Stowe Mountain Resort on the Haselton Trail and ascends up Haselton until meeting up with the South Link Trail.  The South Link trail is across Toll Road at the far end of the parking lot on the right side.  You will have to cross Toll Road to get to South Link (note that it does not go up the "double track" closer to Haselton - you have to go about 50' further down Toll Road to get to the parking lot, where you will see the sign for South Link). After taking South Link for 0.6 miles, you will turn right (north) onto the Forehead Bypass Trail heading north until you meet up with the Long Trail.  At the Long Trail, turn left and head south to the Forehead of Mount Mansfield. Always stay on the trail and use the rocks for your footing. Do not step on the fragile tundra at these elevations.

After reaching the Forehead, you will begin your descent into Underhill by turning right onto the Maple Ridge Trail.  Pay attention - there are various spur trails off of Maple Ridge, but you will simply stay on Maple Ridge. At the bottom of this technical descent, you will pop out onto a Civilian Conservation Corps (CCC) Road, which will bring you north over toward Sunset Ridge.  After a very brief segment (less than one tenth of a mile) on Sunset Ridge, you will stay on Sunset Ridge (left) to begin another grueling ascent up Mount Mansfield (the Double Up part of this race).  Do not go up Laura Cowles Trail. At the top of Sunset Ridge, you will again meet up with the Long Trail and head south (right) on the Long Trail until taking a right onto the Subway Trail, which will connect you to the Canyon North Extension.  After Canyon North, you will turn left onto Halfway House Trail up to the Long Trail. Turn right on the Long Trail to head south.

Once back on the Long Trail for approximately one-tenth of a mile, you will pop out onto a gravel road. Turn right on this road and follow it for less than 1/2 mile until you see see the Long Trail enter the woods again on the right. Almost immediately after re-entering the woods, you will meet up with the northern intersection of the Forehead Bypass Trail.  Take a left onto the Bypass Trail until meeting up with South Link again, where you will take a left to descend back down Stowe Mountain Resort.  After South Link, you will be on Haselton again for a short period before turning a hard-left onto Rimrock (an alpine ski trail).  *Note* The grass is a bit high for the first few hundred yards of Rimrock, so take your time as you navigate through the water bars and rocks.  It is also soggy, so your feet will likely get wet.  Luckily, you'll nearly be finished by this point!

When Rimrock meets Perry Merrill, you will go downhill (right) on Perry Merrill briefly before turning left to follow the gravel/rocky "work road" down to the base instead of continuing on the overgrown Perry Merrill ski trail.  This gravel road basically follows the "Switchback" ski trail.  It will be marked accordingly.  Follow the orange arrows down to the finish line and bask in your glory!

​Hiking poles are permitted, but must be carried at all times (no stashing along the course).  Music of any kind (earbuds or otherwise) is not permitted.

"This course is as painful as it is beautiful, and there's no denying its wow factor. How often do you get to run a legitimate race over sections of the Long Trail, America's oldest long-distance hiking trail?"
-Double Up Creator RJ Thompson


Registration Fees  |  $95 until May 31, 2021
Like most races, the sooner you register the more you save.  Beginning June 1, the fee goes up to $105. Registration closes on July 22.

Rain Date  |  Sunday, August 1, 2021
But I can run in the rain, why a rain date?  While July is generally dry in Vermont, the potential for rain does exist.  If the event organizers and/or trail managers deem the course too wet to run, the race will be postponed to the following weekend.  Yes, most races can be run in the rain, but the trails utilized by this race are susceptible to erosion, and we aim to do our best to protect them and follow the guidance of the Green Mountain Club by not running in excessively muddy conditions.  No refunds will be given if you can't make it to the rain date and/or it rains again on the rain date of 8/1.

The Course  |  ~11 miles ,  ~5,000' vertical gain
When you pack in around 5,000' of elevation gain on some of the most challenging terrain your feet can find, you know you're in for an adventure.  The race starts at the base of Stowe Mountain Resort and ascends Mozo via the Haselton Trail.  From there, you'll link up with various spur trails before descending into Underhill (the other side of Mozo).  After a short run on some more forgiving terrain, you'll begin your approach back up the grueling Sunset Ridge Trail.  Once you reach the Long Trail, you'll link up with some more rugged spur trails before beginning your descent back down the Stowe side via Rimrock and Perry Merrill. Check out the course page for more information as well as the race map.

​If you think running a basic half-marathon is a pre-requisite for this course, you are mistaken.  You should be familiar with mountain running, steep climbs and descents, and negotiating rugged, exposed terrain before considering this race.  It will take much longer than a half-marathon (for some a full marathon), and it will be much harder.

Safety  |  Remote Areas
You will be running in remote areas on trails that are not accessible via motorized vehicle.  The terrain is rugged, technical, slippery, steep, rocky, and full of roots.  You will not be running the entire course because you simply won't be able to do so.  All runners should carry a cell phone in their pack/hydration vest or belt, and should you become injured or completely lost, dial 9-1-1 for rescue.  The course will be marked to help prevent going off trail.

Capacity  |  Limited to 70 Racers
Because we want to respect the fragile environment on which we'll be racing, the race is capped at 70 participants. The high alpine tundra is a delicate ecosystem, and all racers must remain on the trail at all times.  DO NOT attempt to go off trail to pass someone or to go around members of the public who may be out enjoying a morning hike. Runners found abusing the unique privilege to race on this beautiful terrain by disrespecting the trails and its users will be disqualified, and no refund will be issued.

Due to the capacity limit, you will be required to enter your fastest half-marathon, marathon or ultra-marathon time when you register.  If you do not race often, you may upload a screen shot of a Strava/Suunto or similar route tracking software validating your distance and time credentials. Times must be no more than two years old (we don't care how fast you were in 1999 :-)  And if you're an ultra-runner, awesome.  Simply enter your best time from the past two years so we can confirm you're good to go.  With so many different ultras out there, we just need to know you finished with a respectable time. The general qualifying times are below (they will naturally be slower if you ran a race with lots of elevation - that is OK).

Men half-marathon - 1:45:00  |  Full marathon - 3:30:00
Women half-marathon - 2:00:00  |  Full marathon - 4:00:00
Ultra-marathon: Depends on distance and total elevation gain.

You will be notified if the results you provided are not adequate.

Start Time  |  6:30 AM
The first wave of 10 runners will start at 6:30 AM sharp.  After that, racers will start in 10-minute intervals until the final wave has departed at 7:30 AM.  This is to allow racers time to disperse along the course and keep in compliance with the Green Mountain Club's policies for groups larger than 10. Your wave placement will be determined by the race time you provide when you register.

Prizes  |  You know it!
The top three male and female finishers will receive awards.  Additionally, the oldest and youngest runners will receive an award, though you must be at least 18 years of age to compete.  There will also be a raffle with various prizes giving all racers the chance to win something during the awards ceremony.

What do I get for racing?  |  Glory
Ok, you'll also get your race packet and a race t-shirt (new this year!). Plus, there's a good chance you'll win a prize in the raffle given the small amount of racers we're allowed to have.

Refunds and Transfers
The bulk of all costs associated with producing an event are incurred up front (before the race even happens).  For that reason, there will be no full refunds given, but we do offer a 50% refund until June 30.

After that, there will be no refunds issued.  No refunds will be given if you can't make it to the rain date and/or it rains again on the rain date of 8/1.  There will be no race transfers. We repeat, there will be no refunds issued after June 30.