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⏵ Course guide · Central New Hampshire loop 50K

Spaulding Woods 50K Course Guide

Spaulding Woods is a six-loop 50K on the Spaulding Academy campus in Northfield, New Hampshire, and it is worth being upfront about what it is: central New Hampshire lowland forest, not a mountain course. Six 5.6-mile loops add up to about 34 miles and roughly 4,400 feet of cumulative climbing on technical singletrack. I will walk you through the loop and the format, then give you a pacing and fueling plan built for a repeated-loop, cupless, no-pacer race. There are free calculators along the way to dial in your own numbers.

⏵ At a glance

Spaulding Woods 50K quick facts

Date
Saturday, July 11, 2026
Location
Spaulding Academy campus, Northfield, New Hampshire (central NH lowland forest)
Distances
50K, run as six 5.6-mile loops (about 34 miles total)
Elevation gain
About 4,400 ft cumulative across the six loops
Cutoff
10-hour overall limit, strict 4 PM cutoff to start lap 6
Entry style
Cupless race (bring your own cup/bottle), pacers not allowed

These facts come from UltraSignup, the race's primary home online. Independent sourcing beyond that is thin, so check the current date, cutoffs, and race-day details before you commit. Race logistics change year to year.

The course: six loops, honest lowland forest

The 50K is six loops of about 5.6 miles each around the Spaulding Academy campus in Northfield, adding up to roughly 34 miles and about 4,400 feet of cumulative climbing. This is central New Hampshire lowland forest, technical singletrack with some doubletrack mixed in, not mountain terrain, and there is no shame in saying so. The challenge is footing and repetition, not elevation.

The loop: rocks, roots, and footbridges, over and over

Each 5.6-mile loop runs technical singletrack with rocks, roots, and footbridges, and some doubletrack sections mixed in. It is not flat and it is not easy, but it is also not a mountain profile. What makes Spaulding Woods hard is running the same technical footing six times, tired legs make more mistakes on lap five than lap one.

Because it is a loop course, you pass through the start/finish area after every lap, which is genuinely useful: you can manage drop bags, change shoes, and check your splits against the cutoff without needing crew stationed out on the course.

Pacing the repetition: even loops beat a fast start

Six loops means six chances to get pacing wrong the same way. The common mistake is running the first two loops too fast because the legs feel fresh and the footing feels manageable, then paying for it on loop four or five when the same rocks and roots start catching tired feet. Aim for even loop splits rather than a fast start and a defensive finish.

With about 4,400 feet of cumulative gain spread across six loops, no single climb defines the day. It is the accumulation, lap after lap, that adds up.

Cupless and no pacers: plan your own support

Spaulding Woods is a cupless race, so bring your own cup or bottle to aid stations rather than expecting one to be handed to you. Pacers are not allowed at any point, so every loop is on you. Both of these are easy to plan around if you know about them ahead of time, and easy to get caught out by if you do not.

Pacing strategy for a six-loop technical 50K

With no major climbs to manage, Spaulding Woods is about consistency across six repeated efforts on technical footing, not about pacing a single big grade.

Use your loop splits as your pacing feedback

Because the course repeats, your own lap times are the best pacing tool you have. If loop two is meaningfully faster than loop one, you are probably going out too hard for a race that rewards even effort across six trips around the same technical ground. A grade-adjusted pace still helps you translate rolling terrain into honest per-loop targets even without big mountain climbs.

Build a realistic finish window against the 4 PM cutoff

The strict cutoff to start lap 6 at 4 PM is the number that matters most here, not the overall 10-hour limit. Work backward from your loop pace to figure out whether you will clear that 4 PM checkpoint with room to spare. A vert-aware finish prediction that accounts for the cumulative climbing across six loops gives you a more honest number than assuming your flat 50K time will hold.

⏵ Free tools to pace this course

Fueling strategy for a cupless loop race

Most runners are out on Spaulding Woods for somewhere around 5 to 10 hours. The loop format actually makes fueling easier to manage than a point-to-point course, if you plan around it.

Carbs: use your drop bag every lap

Aim for around 60 to 90 grams of carbohydrate per hour. Because the loop brings you back to the start/finish every 5.6 miles, you can restock food and fluid every single lap instead of carrying six loops worth at once. Use that to your advantage: pack your drop bag by lap and keep intake steady rather than loading up early and running dry on lap five.

Bring your own cup and plan sodium for the conditions

Since the race is cupless, carry a collapsible cup or a soft flask you can refill at aid, and do not assume you will be handed anything. Scale sodium to the day's heat, generally in the 300 to 700 milligram per liter range, and adjust it loop to loop if the day turns out hotter than expected.

⏵ Build your fueling plan

Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and the six-loop format 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 six-loop course profile, and your projected splits. Summit Line reads your real training, builds a plan for the repeated technical terrain, and rehearses your fueling so race day is something you execute, not guess at.

Start free →Explore the demo

Spaulding Woods 50K FAQ

How hard is the Spaulding Woods 50K?

Spaulding Woods is a technical, repeated-loop 50K in central New Hampshire, not a mountain race. It is honestly lowland forest, six 5.6-mile loops for about 34 miles total with roughly 4,400 feet of cumulative climbing, rocks, roots, and footbridges on singletrack rather than big vertical relief. The challenge here is technical footing and the mental grind of six loops, plus a strict 4 PM cutoff to start your sixth lap inside the 10-hour overall limit.

Is Spaulding Woods a mountain race?

No, and it is worth saying plainly. Spaulding Woods runs through central New Hampshire lowland forest on the Spaulding Academy campus, not the White Mountains or any significant peak. The 4,400 feet of cumulative gain comes from rolling technical terrain repeated across six loops, not sustained mountain climbing. If you are looking for a big-vert mountain 50K, this is not it, but if you want a technical, honest trail 50K closer to home, it delivers that.

How does the six-loop format work?

The 50K covers six loops of about 5.6 miles each around the Spaulding Academy campus, adding up to roughly 34 miles total. That is a bit longer than a standard 50K (31 miles), so plan and fuel for the real distance. The format means you pass through the start/finish area repeatedly, which makes it easy to manage drop bags and check your own pace, but it also means the race does not let up mentally the way a point-to-point course might.

How should I fuel for the Spaulding Woods 50K?

Plan for a 5 to 10 hour effort depending on your pace across the six loops. Aim for roughly 60 to 90 grams of carbohydrate per hour and sodium scaled to conditions, generally 300 to 700 milligrams per liter depending on heat and your sweat rate. Because the race is cupless, you need to carry your own cup or bottle and manage your own fluid at each aid pass, so build a hydration plan around the loop structure, not around assuming a cup will be handed to you. Run your numbers with the free ultra fueling calculator.

What are the cutoff times for the Spaulding Woods 50K?

The race has a 10-hour overall limit, with a strict cutoff of 4 PM to start your sixth and final loop. Because the course is loops, this cutoff is easy to track against your own lap splits, so use your first few loops to calculate whether you are on pace to start lap 6 before 4 PM.

Are pacers allowed at Spaulding Woods?

No. Pacers are not allowed at any point in the race, so plan to run every loop on your own. The race is also cupless, meaning you need to bring your own cup or bottle to aid stations rather than relying on cups being provided.

This guide is independent and for planning only. The course details, dates, cutoffs, and race-day logistics 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.