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⏵ Course guide · PA Wilds mountain trail

Slate Run Trail Race Course Guide

The Slate Run Trail Race is a remote 25K and half marathon that share a start on rugged mountain singletrack through the Algerine Wild Area and the Black Forest Trail\'s Red Run section, deep in the Pine Creek watershed of Tiadaghton State Forest. A hard cutoff at Manor Fork, roughly mile 9, decides who continues on toward the full 25K and who gets redirected onto the half. I will walk you through the course first, then give you a pacing and fueling plan built around that split. There are free calculators along the way to dial in your own numbers.

⏵ At a glance

Slate Run Trail Race quick facts

Date
Early June (2026: Saturday, June 6)
Location
Slate Run, Tiadaghton State Forest (Algerine Wild Area, Black Forest Trail Red Run section), Pine Creek watershed, PA
Distances
25K (Granite Division) and half marathon (Limestone Division), shared start
Elevation gain
Not published by the organizer; expect sustained mountain climbing on remote singletrack
Mid-course cutoff
Manor Fork camps (mile 9) by noon, or you are redirected onto the half marathon course
Entry style
Capped at 400 entrants, opens on UltraSignup roughly 6 months out, strict no-refund and no-bandit policy

These facts come from the official race site. Check the current date, cutoffs, and aid stations in the race-day details before you commit. Race logistics change year to year.

The course: one start, a hard split at mile 9

The 25K (Granite Division) and half marathon (Limestone Division) start together on remote mountain singletrack through the Algerine Wild Area, picking up the Black Forest Trail\'s Red Run section and streambed crossings early on. Around mile 9, at the Manor Fork camps, the two races split. Miss the cutoff there and you are redirected onto the shorter half marathon course instead of continuing on the 25K.

The shared start: remote singletrack and streambed

Both distances open on the same rugged trail, deep in Tiadaghton State Forest, with real vistas and streambed sections mixed into the singletrack. This is not a course with quick road access if things go wrong, so come ready for genuine backcountry conditions from the first mile.

Footing changes with the streambed crossings, so expect wet rock and uneven ground on top of the usual rooty, rocky Pennsylvania trail surface. Quick feet matter here as much as fitness does.

Manor Fork: the split that decides your race

This is the heart of the race for anyone chasing the full 25K. Reach the Manor Fork camps, roughly mile 9, by noon and you continue on toward the Old Supply Trail. Miss it and you are rerouted onto the half marathon course instead, no matter how you feel. That makes the pace you carry through the first 9 miles the single biggest strategic decision of the day, more than anything that happens after the split.

Beyond the split: the streambed and Old Supply Trail

Once the 25K breaks off, the course continues up a streambed and onto the Old Supply Trail, keeping the technical, climbing character of the race going rather than easing off. Save something in your legs for this stretch. Runners who spend everything trying to make the mile 9 cutoff often find the back half of the 25K is where that decision catches up with them.

Pacing strategy around the mile 9 cutoff

Slate Run is not about hitting a flat-ground pace chart. It is about arriving at Manor Fork with the full 25K still available to you, and having enough left to run the technical miles after the split.

Race the first 9 miles honestly, not conservatively

The noon cutoff at Manor Fork is not generous on remote, technical singletrack, so treat the opening miles as a real effort, not a warmup. At the same time, do not empty the tank trying to beat the cutoff by a wide margin. A grade-adjusted pace target for this terrain helps you find the effort that gets you to Manor Fork with room to spare and legs still capable of the climbing that follows.

Plan your race around two possible outcomes

Because missing the mile 9 cutoff reroutes you onto the half marathon whether you like it or not, it is worth mentally preparing for both outcomes before race day rather than fixating only on the full 25K. Build a realistic finish window for the 25K with a vert-aware time estimate, and know what a strong half marathon effort looks like too, so a reroute at Manor Fork is a different race, not a ruined one.

⏵ Free tools to pace this course

Fueling strategy for a remote mountain course

The combination of climbing, technical footing, and real remoteness means you cannot count on frequent aid the way you might on a more accessible course. Plan to carry more than you think you need.

Carbs: fuel for climbing effort, not flat miles

Aim for 60 to 90 grams of carbohydrate per hour, on the higher end if your gut is trained for it, since the sustained climbing and technical terrain push your effort well above what the raw distance suggests. Fuel steadily through the opening miles rather than waiting until after the Manor Fork split, since the climbing that follows is not the place to start catching up on calories.

Sodium and fluid: carry extra for the remote stretches

Plan sodium in the 300 to 700 mg per liter range, pushed higher if June turns warm and humid in the Pine Creek watershed. Because the course runs through remote, streambed-heavy terrain with limited outside access, carry more fluid and calories than you think you need between aid stations rather than banking on a quick resupply.

⏵ Build your fueling plan

Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and this remote course 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 remote Pine Creek watershed course, and your projected splits into the mile 9 cutoff. Summit Line reads your real training, builds a plan for the climbing, and rehearses your fueling so race day is something you execute, not guess at.

Start free →Explore the demo

Slate Run Trail Race FAQ

How hard is the Slate Run Trail Race?

Slate Run is a genuinely remote, rugged mountain trail race, not a beginner course. Both the 25K and the half marathon share a start on singletrack through the Algerine Wild Area and the Black Forest Trail's Red Run section in Tiadaghton State Forest, with streambed sections and real vistas, and the 25K keeps climbing up the Old Supply Trail after the split at Manor Fork. The organizer does not publish an elevation gain figure, but the terrain and the mile 9 cutoff both signal this is built for prepared trail runners, not a first race.

How much climbing is in the Slate Run Trail Race?

The official race site does not publish an elevation gain number for either distance. What is confirmed is that the course runs through the Algerine Wild Area and the Black Forest Trail Red Run section on remote mountain singletrack, and the 25K continues up a streambed and the Old Supply Trail once it splits from the half. Plan for sustained climbing and technical footing rather than a specific vert figure, and treat any number you see elsewhere as unconfirmed.

How should I fuel for the Slate Run Trail Race?

Treat this as a multi-hour effort on remote, technical terrain with real climbing, so aim for 60 to 90 grams of carbohydrate per hour and sodium in the 300 to 700 mg per liter range, adjusted up if June turns warm in the Pine Creek watershed. Because the course is remote with streambed sections and limited road access, carry more than you think you need between aid rather than counting on a quick resupply. Dial in your own numbers with the free ultra fueling calculator.

What are the cutoff times for the Slate Run Trail Race?

The key cutoff is at the Manor Fork camps, roughly mile 9, which you need to reach by noon. If you miss it, you are redirected onto the half marathon course instead of continuing on the 25K. That makes the first 9 miles the part of the race where your pacing actually matters most, since arriving at Manor Fork with time to spare is what keeps the full 25K on the table.

What is the terrain and weather like at Slate Run?

Expect remote, rugged mountain singletrack through the Algerine Wild Area and the Black Forest Trail's Red Run section, with streambed crossings and real vistas along the way. After the mile 9 split, the 25K continues up a streambed and onto the Old Supply Trail, which keeps the technical climbing going into the back half. Early June in the Pine Creek watershed can run warm and humid, and the remoteness of the course means you should not expect frequent access to help or shortcuts.

Is the Slate Run Trail Race a good first trail race?

Not really. The remoteness, the technical streambed and singletrack footing, and the hard mile 9 cutoff onto the shorter course all point to a race built for runners with some trail experience already, not a first outing. If you are new to trail racing, the shared-start half marathon option is the gentler entry point here, but even that runs through genuinely rugged Pennsylvania mountain terrain, so come with real time on technical trail under your legs.

This guide is independent and for planning only. The course details, dates, cutoffs, and aid stations come from public sources and can change year to year, so confirm the current specifics with the official race before you register or run. The fueling and pacing advice is general and not medical advice.