⏵ Course guide · Nevada side of Lake Tahoe
The Marlette 50K starts and finishes at Spooner Lake on the quieter Nevada side of Lake Tahoe, circling Marlette Lake on pristine Sierra single-track with 360-degree views of the lake, Marlette Lake, and the Carson Valley and Range. The Marlette 10 Miler shares the start and loops Spooner Lake with an out-and-back on the Tahoe Rim Trail. I will walk you through both courses first, then give you a pacing and fueling plan built around the published intermediate cutoffs, plus free tools to dial in your own numbers.
These facts come from the official Tahoe Trail Running / Big Blue Adventure event page. Total elevation gain is not published for either distance. Course and logistics details can change year to year, so confirm the current specifics before you commit.
Both distances start at Spooner Lake in the Spooner Backcountry of Lake Tahoe Nevada State Park, a section of Tahoe that sees far less foot traffic than the busier California shore.
From Spooner Lake, the 50K heads out onto pristine Sierra single-track that circles Marlette Lake, delivering 360-degree views of Lake Tahoe itself, Marlette Lake, and the Carson Valley and Range beyond. Seven aid stations support the 31-mile route at roughly miles 7, 12, 14.7, 20, 24.3, 25.8, and 29.6, giving you frequent, well-spaced chances to refuel on true Sierra backcountry trail.
Starting just five minutes after the 50K, the 10 Miler loops around Spooner Lake before transitioning to an out-and-back section on the Tahoe Rim Trail, with views of North Canyon, Lake Tahoe, and Snow Valley Peak. The course completes its Spooner Lake loop again near the finish, so both ends of the race deliver the same scenic lake views that bookend the day. Four aid stations cover the distance at roughly miles 3.8, 5.4, 8.6, and the finish at mile 10.
The 50K publishes two intermediate cutoffs rather than a single finish deadline, which gives you real checkpoints to plan against instead of guessing at your overall pace.
You need to reach mile 14.8 (Aid Station 3) within 4 hours 30 minutes and mile 20 (Aid Station 4) within 6 hours of the 7:30 AM start. Back your pacing plan into those two numbers rather than the overall 4 PM event window, since the intermediate cutoffs are the tighter constraint for most mid-pack runners. A grade-adjusted pace target for the Marlette Lake single-track gives you an honest number to check against both checkpoints as the race unfolds.
The race's own schedule shows the first 50K finisher typically crossing well before 11:30 AM, under 4 hours, which tells you the course rewards strong Sierra trail fitness. That is not your pacing target unless you are racing for the podium; use it instead to understand how much faster the leaders move through the same terrain, and set your own realistic split off a race-time prediction built from your actual fitness.
⏵ Free tools to pace this course
August at Lake Tahoe elevation is generally mild, but a 7:30 AM start means the later miles of the 50K will run warmer than the opening ones.
With aid stations roughly every 4 to 6 miles across the 50K, you have plenty of chances to stay on top of a steady carbohydrate intake, roughly 60 to 90 grams per hour, without carrying heavy reserves. Stations stock water, electrolyte drink, salty snacks like chips and pretzels, pickles, cola, ice, and gels, a solid mix of real food and standard race fuel.
Keep sodium in the 300 to 700 mg per liter range through the morning, and lean toward the higher end as you move into the afternoon miles if the day warms up. The Spooner Backcountry offers little shade in stretches, so treat any exposed sections as a cue to bump your sodium and fluid intake rather than waiting until you feel the effects of the heat.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and a Sierra summer 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 race-day plan built around YOUR fitness and this Marlette Lake course profile, with your projected splits checked against the mile 14.8 and mile 20 cutoffs. Summit Line reads your real training, builds a plan for Sierra single-track, and rehearses your fueling so race day is something you execute, not guess at.
It runs on pristine Sierra single-track through the Spooner Backcountry of Lake Tahoe Nevada State Park, starting and finishing at Spooner Lake and circling around Marlette Lake with 360-degree views of Lake Tahoe, Marlette Lake, and the Carson Valley and Range. It is on the quieter Nevada side of Tahoe rather than the more crowded California shore, which gives it a different, less trafficked feel than many Tahoe-area trail races.
The official race page does not publish a total elevation gain figure for the 50K or the 10 Miler, so treat any number you see elsewhere as unverified. What is confirmed is that the course runs through genuine Sierra high country in the Spooner Backcountry, so expect meaningful climbing consistent with terrain around Marlette Lake and the Tahoe Rim Trail, even without an exact published total.
Two intermediate cutoffs are published: you need to reach mile 14.8 (Aid Station 3) within 4 hours 30 minutes of the 7:30 AM start, and mile 20 (Aid Station 4) within 6 hours. The overall event window runs from the 7:30 AM start to 4:00 PM, an 8.5-hour window, though the race's own schedule shows the first 50K finisher typically crossing well before 11:30 AM, so the two intermediate cutoffs are the real pacing checkpoints to plan around.
The 10 Miler starts just 5 minutes after the 50K and loops around Spooner Lake before heading out on an out-and-back section of the Tahoe Rim Trail, taking in views of North Canyon, Lake Tahoe, and Snow Valley Peak. It finishes by completing the Spooner Lake loop, so you get a scenic bookend at both the start and the end. Four aid stations support the distance, at approximately miles 3.8, 5.4, 8.6, and the finish at mile 10.
August at Lake Tahoe elevation runs generally mild, but a 7:30 AM start means you will be climbing into warmer afternoon temperatures by the later miles. 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 day turns warm. The aid stations stock water, electrolyte drink, salty snacks like chips and pretzels, pickles, cola, and gels, spaced roughly every 4 to 6 miles across the 7 stations, giving you frequent chances to reset your intake. Build your specific numbers with the free ultra fueling calculator before race day.
The frequent aid station spacing (7 stations over 31 miles) and the clearly staged intermediate cutoffs make it a reasonably beginner-friendly 50K if you have some trail experience and are comfortable with Sierra elevation. The course is a step up in remoteness from a groomed park loop, so make sure your navigation and self-sufficiency between aid stations are solid before you toe the line, and use the two published cutoffs at mile 14.8 and mile 20 as your own pacing checkpoints rather than waiting until you feel behind.
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<a href="https://runsummitline.com/guides/marlette-50k">The Marlette 50K & 10 Miler course guide</a><iframe src="https://runsummitline.com/embed/race/marlette-50k" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="Marlette 50K & 10 Miler course guide by Summit Line"></iframe>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.
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