⏵ Course guide · Santa Cruz Mountains redwoods
Santa Cruz Trail Run climbs about 3,250 feet over 18.2 miles through Henry Cowell Redwoods State Park, twisty singletrack under giant redwoods, a sandy ridge stretch, and two crossings of the San Lorenzo River. I will walk you through the course first, then give you a pacing and fueling plan built for technical, tree-covered climbing. There are free calculators along the way to dial in your own numbers.
These facts come from the official Inside Trail Racing event page. Check the current year details, cutoffs, and aid stations before you commit. Race logistics change year to year.
The 30K, Half, and 10K all run through Henry Cowell Redwoods State Park, climbing the Santa Cruz Mountains on mostly twisty singletrack under a canopy of giant second and third-growth redwoods.
Coiling singletrack opens up to wider roads and paths, and even a stretch of sand, as the course crosses the "golden half-mile" ridge in loose footing. Ocean breezes pour in from the Santa Cruz coast throughout, a nice contrast to the dense tree cover elsewhere on the course.
Both the 30K and Half Marathon cross the San Lorenzo River twice, a feature the race organizers call an "esteemed pleasure." Expect wet feet and a change of footing texture right in the middle of the climbing, so plan your shoe choice and any blister prevention accordingly.
This is a cupless event, so carry at least one 20-ounce bottle. Aid stations sit roughly every 5 to 6 miles with Gu gels and chews, Stroop Waffles, trail mix, boiled potatoes with salt, and Skratch Labs Sports Hydration, enough density that you can travel light between stops.
About 3,250 feet of gain over 18.2 miles inside a 6 hour cutoff leaves real margin, but the moderately technical footing under the tree canopy still deserves respect.
The course alternates between twisty climbing singletrack and faster fire road, so a flat-ground pace target will not tell you much. A grade-adjusted pace target gives you an honest number for the climbs, so you are not blowing up on the way up to the ridge.
A vert-aware finish prediction, built off the roughly 3,250 feet of gain, is a better guide than a flat 30K time. Check it against the 2:30 PM course closure early enough that you still have room to adjust effort if the river crossings or sand section slow you more than expected.
⏵ Free tools to pace this course
An 8:30 AM start under redwood canopy keeps things cool early, but the sand ridge and exposed sections can heat up fast once the coastal fog burns off.
Aim for roughly 60 to 90 grams of carbohydrate per hour. With aid every 5 to 6 miles carrying both gels and real food, you have flexibility to adjust what you are eating as the day goes on rather than committing to one plan for the whole 18.2 miles.
Sodium in the 300 to 700 mg per liter range covers most runners. The exposed ridge and sand stretch are where you will feel the sun most, so top off fluids and electrolytes at the aid station just before that section rather than relying only on what you are carrying.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and this redwoods-to-sand 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 exact redwoods climbing profile, and your projected splits. Summit Line reads your real training, builds a plan for technical tree-covered terrain, and rehearses your fueling so race day is something you execute, not guess at.
The 30K climbs roughly 3,250 feet over 18.2 miles of moderately technical dirt trail through Henry Cowell Redwoods State Park, mostly twisty singletrack climbing through the Santa Cruz Mountains. It is a real workout but not an extreme one by Inside Trail standards, and the 6 hour cutoff gives most trained ultra runners real room. The two San Lorenzo River crossings and a stretch of loose sand along the ridge add variety most redwoods races do not have.
The 30K carries about 3,250 feet of gain over 18.2 miles, the Half Marathon about 2,625 feet over 13.5 miles, and the 10K about 980 feet over 6.0 miles. Most of the climbing comes from twisty singletrack working up through the Santa Cruz Mountain Range, with some dirt fire road and a brief paved descent mixed in.
This is a cupless event, so bring your own bottle or reusable cup. Aid stations sit every 5 to 6 miles and carry Gu Energy gels and chews, Stroop Waffles, trail mix, boiled potatoes with salt, PB&J, and Skratch Labs Sports Hydration. For a 30K on a 6 hour clock, aim for roughly 60 to 90 grams of carbohydrate per hour, and keep sodium in the 300 to 700 mg per liter range, leaning higher if the late-August coastal heat builds. Build your numbers with the free ultra fueling calculator before race day.
The race carries a 6 hour time limit, and all runners must be off the course by 2:30 PM given the 30K start at 8:30 AM. That leaves a bit under 20 minutes per mile average pace for the full 18.2 mile course, real margin for a technical redwoods 30K.
Giant redwoods dominate the course, with twisty singletrack that opens up to fire roads, a stretch of loose sand along a ridge locals call the "golden half-mile," and two crossings of the San Lorenzo River for the 30K and Half Marathon. Expect moderately technical footing throughout, climbing hills within the Santa Cruz Mountain Range under a heavy tree canopy.
The 30K is a reasonable first-ultra option if you have some trail experience. About 3,250 feet of gain over 18.2 miles is moderate, the 6 hour cutoff gives real buffer, and the course stays mostly runnable outside a few technical climbing sections. The river crossings and sand stretch are more novelty than obstacle, small variety that makes the course memorable without making it dangerous.
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<a href="https://runsummitline.com/guides/santa-cruz-trail-run">The Santa Cruz Trail Run course guide</a>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.