⏵ Course guide · Forest Park, Portland
Stumptown Trail Runs, formerly Trail Factor 50K, runs entirely inside Portland's 5,200-acre Forest Park over Memorial Day weekend, with a 50K on the iconic Wildwood Trail carrying almost 4,000 feet of gain and a Half Marathon over about 1,800 feet of gain and loss. I will walk you through the course first, then give you a pacing and fueling plan built for a climbing-heavy city ultra. There are free calculators along the way to dial in your own numbers.
These facts come from the official Go Beyond Racing event page. The exact 2027 date is not yet officially posted, check before you register, and confirm current cutoffs and aid stations before you commit.
Both races start a quarter mile up Leif Erikson Drive from the gate at the top of NW Thurman St and stay entirely inside Forest Park's 80-plus miles of trail.
The 50K carries almost 4,000 feet of elevation gain and includes the iconic Wildwood Trail, a designated National Recreation Trail, along with lesser-known singletrack elsewhere in the park. Despite being inside city limits, this is a genuine climbing day.
The Half Marathon covers about 1,800 feet of gain and loss on the same Forest Park trail network, a real but far more approachable version of the 50K climbing profile.
Go Beyond Racing states plainly that these are running events, not walking races, and poles are not allowed on either distance. Plan your gear and pacing strategy around continuous running rather than a hike-run approach.
Almost 4,000 feet of gain on the 50K, packed inside a city park, means the terrain deserves more respect than the "urban" label suggests.
With no poles allowed, your climbing pace on the Wildwood Trail sections needs to be a running pace you can sustain, not a hike you plan to fall back on. Use a grade-adjusted target to set a realistic effort for the climbs rather than pacing off flat-ground numbers.
⏵ Free tools to plan your effort
Late May in Portland can run mild or warm, and almost 4,000 feet of climbing on the 50K burns through carbohydrate faster than a flatter course of the same distance.
Aim for roughly 60 to 90 grams of carbohydrate per hour on the 50K, and sodium in the 300 to 700 mg per liter range, adjusted for a late-May Portland day. The Half Marathon's shorter distance still carries real climbing, so do not skip a fueling plan just because the distance looks approachable on paper.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and a late-May Portland day 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 training plan built around YOUR fitness and the kind of sustained climbing this Forest Park course demands. Summit Line reads your real training, builds the durability your chosen distance asks for, and rehearses your fueling so race day is something you execute, not guess at.
Stumptown Trail Runs (formerly Trail Factor 50K) runs over Memorial Day weekend, around May 29 to 31, 2027, with the Half Marathon on Saturday and the 50K on Memorial Monday. Go Beyond Racing has not yet officially posted the exact date on the race page, so confirm before you register, but the race has held this Memorial Day weekend slot for years.
Both races run entirely inside Forest Park, a 5,200-acre park in the middle of Portland with over 80 miles of trails. The 50K uses the iconic Wildwood Trail, a National Recreation Trail, along with lesser-known singletrack elsewhere in the park. Both races start a quarter mile up Leif Erikson Drive from the gate at the top of NW Thurman St.
The 50K carries almost 4,000 feet of elevation gain, a genuine Pacific Northwest trail ultra test packed into a course that never leaves city limits. The Half Marathon carries about 1,800 feet of gain and loss, a real but manageable trail challenge. Poles are not allowed on either distance, since these are run as running events, not walking races, so expect a course that rewards runners comfortable moving continuously on rolling singletrack.
No. The race states plainly that these are running events, not walking races, and poles are not permitted on either the 50K or the Half Marathon.
Forest Park's urban location is a real advantage for a first ultra: you are never far from the start/finish area, aid, or a way out if you need one, even with almost 4,000 feet of climbing on the course. The Wildwood Trail miles are well-maintained singletrack rather than remote wilderness, which makes the logistics forgiving even as the elevation gain makes it a genuine test.
With close to 4,000 feet of gain on the 50K, plan a real climbing-day fueling strategy rather than a flat-course one. Aim for roughly 60 to 90 grams of carbohydrate per hour, and sodium in the 300 to 700 mg per liter range, adjusted for a late-May Portland day. Use the free ultra fueling calculator to build your own numbers.
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<a href="https://runsummitline.com/guides/stumptown-trail-runs">The Stumptown Trail Runs course guide</a><iframe src="https://runsummitline.com/embed/race/stumptown-trail-runs" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="Stumptown Trail Runs course guide by Summit Line"></iframe>This guide is independent and for planning only. The course details, dates, and entry rules 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.
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