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Rothrock by UTMB Course Guide

Rothrock by UTMB is the first UTMB World Series race in Pennsylvania, held in Rothrock State Forest near Boalsburg and Happy Valley. The terrain is not new. This ground has hosted the Rothrock Trail Challenge since 2009, through a hiatus and a comeback and now a rebrand under the UTMB banner. I will walk you through the 50K and 25K, be straight with you about what is still settling as the event transitions, and give you a pacing and fueling plan built for central Pennsylvania's rockiest singletrack.

⏵ At a glance

Rothrock by UTMB quick facts

Date
Mid-May weekend (50K Saturday, 25K Sunday); confirm the current year on the official UTMB page
Location
Boalsburg / Happy Valley, PA, Rothrock State Forest
50K distance
53.3 km (about 33.1 mi)
50K elevation gain
1,550 m+ (about 5,085 ft)
25K distance
26.9 km (about 16.7 mi)
25K elevation gain
1,188 m+ (about 3,898 ft)
Cutoffs
Not published at the time of writing; confirm on the official UTMB race page
Series status
First UTMB World Series event in Pennsylvania, part of the Rothrock Trail Challenge lineage founded 2009

Distance and elevation figures come from the official UTMB event page. Cutoffs and entry price were not published at the time of writing. This is a mid-transition event onto the UTMB World Series, so confirm every detail on the official race page before you register.

The course: Rothrock's rockiest singletrack

The 50K covers 53.3 kilometers with about 1,550 meters of gain, and the 25K covers 26.9 kilometers with about 1,188 meters of gain, both through Rothrock State Forest. This is widely regarded as some of central Pennsylvania's best singletrack, which also means some of its rockiest.

Sandstone ridges and technical footing

Expect sandstone ridgelines and extra rocks layered on top of already-technical central Pennsylvania trail. This is not a course where you zone out and let your legs turn over. Quick feet and constant attention to the ground matter as much as raw fitness, especially as the miles add up and your focus starts to slip.

The elevation numbers, 1,550 meters for the 50K and 1,188 for the 25K, understate how much the rocky footing slows real splits compared to smoother trail with similar vert.

Fern valleys, rhododendron tunnels, and streams

Between the technical ridge sections, the course drops through fern-covered valleys and rhododendron tunnels, with stream crossings and cliffside stretches mixed in. If the race falls during mountain laurel bloom, add some involuntary sightseeing to your day. It is genuinely pretty ground, and it will cost you time if you let it.

A course with a 17-year memory

Runners who did this event as the Rothrock Trail Challenge before its 2018 hiatus, or during its 2021 comeback as a Tussey Mountain Ski Patrol fundraiser, will recognize the terrain. What has changed is the branding, the organizational backing, and likely the field size and depth that come with joining the UTMB World Series. The rocks have not gotten any softer.

Pacing strategy for a rocky, climb-heavy 50K or 25K

With over 1,500 meters of gain in the 50K on technical Rothrock singletrack, this course punishes flat-ground pacing assumptions. Run it on effort, not on a splits chart built for smoother trail.

Grade-adjust your effort on the sandstone climbs

Your flat pace does not translate to a sandstone ridgeline climb, and it especially does not translate to descending one at speed. Use a grade-adjusted pace to convert your real fitness into honest targets for the climbing and the technical descents, so you are not guessing at effort on ground this unforgiving.

Build a realistic finish window for the terrain

A 50K or 25K time from a smoother course will not hold up here. The rocky footing and the sustained climbing both add real time beyond what the vert numbers alone suggest. A vert-aware finish prediction gives you a more honest window to plan your day around, especially useful while cutoff details for this event are still settling.

⏵ Free tools to pace this course

Fueling strategy for the 50K and 25K

Neither distance is a sprint, and the technical footing slows you down enough that fueling still matters even on the shorter 25K.

Carbs: dial it in before race day

Aim for roughly 60 to 90 grams of carbohydrate per hour on the 50K, scaled to how many hours you expect to be out there. On the 25K, do not skip fueling just because the distance looks short on paper, the rocky, climb-heavy terrain will slow you more than the number of miles implies. Practice your intake on similarly technical long runs so your gut is not surprised on race day.

Sodium: plan for a May Rothrock day, whatever that brings

Sodium in the 300 to 700 milligram per liter range covers most conditions, and you should lean toward the higher end if the forecast runs warm or humid. Mid-May in central Pennsylvania can swing either way, so check the forecast close to race day and adjust rather than locking in a number months ahead.

⏵ Build your fueling plan

Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and Rothrock's terrain with the free ultra fueling calculator. Browse the rest of the free running tools at the tools hub.

⏵ Train for it with Summit Line

Get a race-day plan built around YOUR fitness, this exact Rothrock course profile, and your projected splits. Summit Line reads your real training, builds a plan for the climbing and the technical footing, and rehearses your fueling so race day is something you execute, not guess at.

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Rothrock by UTMB FAQ

What is Rothrock by UTMB?

Rothrock by UTMB is the first Pennsylvania stop on the UTMB World Series, run through Rothrock State Forest near Boalsburg and Happy Valley. It is not a brand-new race, it carries a 17-year lineage: it started in 2009 as the Rothrock Trail Challenge under PA Trail Dogs, went on hiatus after 2018, came back in 2021 as a Tussey Mountain Ski Patrol fundraiser, and then joined the UTMB World Series. Confirm the current year details on the official UTMB race page, since a mid-transition event like this changes fastest right when it changes ownership.

How hard is Rothrock by UTMB?

The 50K covers 53.3 kilometers with about 1,550 meters (roughly 5,085 feet) of climbing, and the 25K covers 26.9 kilometers with about 1,188 meters (roughly 3,898 feet). Both distances run through central Pennsylvania singletrack loaded with extra rocks, sandstone ridges, and technical footing, so the vert numbers alone understate how much the terrain slows you down.

What is the terrain like at Rothrock by UTMB?

Rothrock State Forest is regarded as some of central Pennsylvania's best singletrack, and also some of its rockiest. Expect sandstone ridgelines, fern valleys, rhododendron tunnels, stream crossings, and cliffside sections, on trail that rewards careful foot placement over raw speed. If the course runs during mountain laurel bloom, add slow-your-roll scenery to the list of reasons your splits will not match a flat-course pace chart.

What are the cutoffs for Rothrock by UTMB?

Cutoff times were not published at the time of writing. This is a mid-transition event, freshly onboarded to the UTMB World Series, so race-day logistics like cutoffs and aid station schedules are worth double-checking on the official UTMB race page close to race day rather than assuming they match the old Rothrock Trail Challenge format.

How should I fuel for Rothrock by UTMB?

For the 50K, plan for several hours of steady effort on technical terrain, and aim for roughly 60 to 90 grams of carbohydrate per hour, adjusted down if you have not trained your gut at the higher end. Sodium in the 300 to 700 milligram per liter range covers most conditions, scaled up if May in Happy Valley runs warm that year. The 25K is shorter but no less technical, so do not skip fueling just because the distance looks manageable on paper.

Is Rothrock by UTMB the same race as the old Rothrock Trail Challenge?

Same forest, same rocky central Pennsylvania singletrack, and organizationally the same lineage, but the event has changed hands and branding more than once. It started as the Rothrock Trail Challenge in 2009, paused after 2018, returned in 2021 under new stewardship, and is now part of the UTMB World Series. If you ran the old event, expect the terrain to feel familiar and the logistics, branding, and possibly qualifying structure to feel new.

This guide is independent and for planning only. Rothrock by UTMB is mid-transition onto the UTMB World Series platform, so dates, cutoffs, pricing, and other logistics are more likely than usual to change from what is published here. Confirm every detail on the official UTMB race page before you register or run. The fueling and pacing advice is general and not medical advice.