Leadville 100: The History of a Legendary High‑Altitude Ultra

Why Leadville matters to the running community

If you care about ultra, run, history and grit, Leadville is one of those races that shows up in every conversation. Born in 1983 from a community need to revive a mining town, the Leadville Trail 100 quickly became both a proving ground and a legend. The race’s DNA—high altitude, long climbs, and community-first roots—still shapes the week in Cloud City today according to the Leadville Race Series history and contemporary reporting in iRunFar’s feature.

Founders, purpose, and early years

Ken Chlouber, Merilee Maupin and Jim Butera launched the original Leadville Trail 100 Run to bring overnight visitors back to Leadville after mine closures left the town struggling. That community-first mission is described in detail on the series’ history page and in a thorough retrospective at iRunFar. The first running drew 45 starters in 1983; what began as a local economic lifeline evolved into an international ultra destination.

How the event grew (and what stayed the same)

Growth came gradually: the 100‑mile run was followed by mountain bike events (the MTB started in 1994) and a full Leadville Race Series with multiple race formats and distances. You still get the same core experience—starting and finishing in town, a brutal out‑and‑back course, and the iconic Hope Pass climb on the run or the Columbine summit on the MTB—while production, live tracking, and athlete services have matured under Life Time’s ownership (the sale to Life Time is covered in iRunFar’s history piece). The Leadville Race Series also documents that evolution on its history section.

Iconic course facts and records you should know

• The run course begins at roughly 10,200 feet and peaks at Hope Pass around 12,500 feet; total elevation gain is north of 15,000 feet on the 100‑mile out‑and‑back course—details are on the official Leadville Trail 100 Run page.
• The Leadville Trail 100 Run course record (men) was shattered in 2024 by David Roche with a time of 15:26:34, and Ann Trason’s historic women’s record (18:06:24, 1994) still features prominently in the race’s lore (see Leadville Trail 100 on Wikipedia).
• The Leadville Trail 100 MTB is similarly iconic; Keegan Swenson and other recent champions firmly established sub‑6 to 6‑hour efforts for top male riders—check the MTB Wikipedia page for the winner lists and historical context.

Leadville in the race calendar: 2025 race dates and registration details (verified)

• Leadville Trail 100 MTB: Saturday, August 9, 2025. Entry fee listed at $525 for solo racers (tandem $625). Official event details and race week schedule are on the LT100 MTB event page.
• Leadville Trail 100 Run: Saturday, August 16, 2025. Entry fee listed at $450. Full race week schedule, cutoffs, and logistics are on the LT100 Run event page.

Both pages include athlete meeting times, packet pickup, drop bag windows, and crew/pacer rules you must know before race week. If you are planning to enter, use the event pages above for registration windows and the lottery/qualification process referenced on the event pages.

Modern logistics every runner should bookmark

Plan your crew, shuttle, and drop bags around the official rules. Key verified items from the event pages:

• Belt buckle standards for the Run: big buckle under 25 hours (chip time), small buckle under 30 hours (chip time) — see the LT100 Run page for details.
• Pacers for the Run are allowed starting at Twin Lakes inbound (mile 61.8), and pacer bibs/wristbands are issued at packet pickup — full pacer rules are available on the Run page.
• The MTB uses a corral start system and awards buckles for a 9‑hour (big) and 12‑hour (small) finish—see the LT100 MTB page for corral times and buckle policies.
• Nutrition partners such as Neversecond and Skratch Labs supply on‑course fuel for both Run and MTB—train with the exact products listed on the official pages to avoid GI surprises (Run on-course nutrition).

Race‑week essentials and weather at 10,000+ feet

Leadville’s August weather swings fast: days in the 70s and nights into the 20s are typical, and storms (including hail or snow near summits) are possible. The event pages explicitly emphasize layering, warm/protective clothing for Hope Pass, and that lightning is a real hazard above tree line—so pack for all seasons and bring a reliable waterproof/breathable shell (Run event page weather & packing notes).

Insider tip: Acclimate for at least 3–5 days if you can. If time is tight, stagger intensity—easy runs plus one moderate threshold day—and consider the racer clinics offered (for MTB, St Vincent Health ran saline IV and sports medicine clinics during race week—see LT100 MTB race info).

Training and race strategy suited to Leadville

1. Altitude specificity: practice long runs or rides at elevation if possible. If you live low, prioritize conservative pacing early and dial in fueling to avoid bonking at high miles.
2. Hill strength + technical descending: the course mixes fire roads and technical trail—work sustained climbing repeats and descending drills.
3. Fueling: use the same gels, drinks, and bars you’ll find on course (Neversecond and Skratch Labs appear on the event menus) so your stomach knows the menu ahead of time (Run nutrition).
4. Cutoff pacing: study the official cutoffs—Leadville enforces multiple split cutoffs (for the Run these include Mayqueen, Outward Bound, Half Pipe, Twin Lakes, Hope Pass, Winfield) so build a pacing plan with buffer time and contingency for slow sections (Run cutoffs & aid details).

Gear and logistics — what winners and experienced finishers swear by

• Lightweight windproof insulation, a hard shell, and warm mountain gloves for Hope Pass. The race pages explicitly warn against attempting Hope Pass without warm clothing (Run packing and weather notes).
• For the Run: practice with drop bags and pacer handoffs matching official drop bag rules—clear plastic bags, labeled, dropped during packet pickup windows as described on the Run page.
• For the MTB: a reliable service plan for your bike is essential; the MTB page highlights local bike shop services and bike shipping options for racers traveling in (LT100 MTB bike shipping & services).

Recent results you should know (context matters)

• Leadville Trail 100 Run: the 2024 men’s course record-holder is David Roche (15:26:34, 2024) and 2024 women’s winner Mary Denholm finished in 18:23:51—see the historical winners and recent champs at Leadville Trail 100 on Wikipedia.
• Leadville Trail 100 MTB: Keegan Swenson has been a dominant force in recent years; consult the MTB Wikipedia page for the year-by-year winners and context on course records.

These results show what the top end of the sport looks like, but remember—Leadville’s culture honors every finish under the official cutoff and celebrates the grit of community racers just as loudly as it does the elites. Information on awards and buckle distribution is available on the official event pages (Run awards & buckles / MTB awards & buckles).

Comparing Leadville to other 100‑mile events (what makes it unique)

• Altitude: Leadville starts above 10,000 feet—this is higher than many iconic 100s (for example, Western States is lower elevation overall). That altitude makes pacing and acclimation the deciding factors.
• Course character: heavy climbing and a high alpine pass (Hope Pass) make it different from flatter or more runnable 100s; the MTB has long climbs like Columbine Mine that define the day.
• Timing: Leadville is mid‑summer (August), which affects training cycles. If you’re chasing a summer ultra calendar, schedule base-building in winter/spring and peak in July–August to hit Leadville fresh.

In short: if you want an ultra that tests altitude, climb endurance, and backcountry logistics—Leadville is one of the purest expressions of that test. The race’s role in the Western Slam and Grand Slam of Ultrarunning underscores its standing in ultra history (Leadville role in larger ultra series).

Insider race‑week tips from race directors and veterans

• Get to town early: packet pickup, expo, and shakeout runs are scheduled across Thursday–Friday in race week. The event pages list mandatory athlete meetings and expo programming—arrive to attend the athlete meeting and expo sessions to pick up local intel (Run event schedule / MTB event schedule).
• Use the official crew locations and shuttles: Leadville enforces four crewing spots to protect trails and the community. Crewing outside those locations risks disqualification; study the crew maps on the event pages.
• Master aid‑station strategy: stock up at crewed aid stations (Outward Bound and Twin Lakes) and carry enough electrolytes between uncrewed stretches.
• Practice night navigation: parts of the Run require trail focus at night—train with your headlamp on technical descents and simulate long night-time efforts.

Ready to plan your Leadville experience? Concrete next steps

1. Choose your event: Run (Aug 16, 2025) or MTB (Aug 9, 2025) — verified event pages: LT100 Run and LT100 MTB.
2. Review entry paths and the lottery/qualification methods on the event pages (the series publishes qualification and lottery info there).
3. Book travel and 3–5 days of arrival to acclimate. Reserve lodging early—Leadville fills fast during race week.
4. Build an altitude-aware training block: include heat acclimation if possible, long climbs, and a minimum of one night run to simulate fatigue and darkness.
5. Study official cutoffs, crew maps, and packing guidance on the race pages so you arrive race‑week ready.

Final thoughts — why Leadville’s history still matters

Leadville’s story is both local and universal: it began as a solution to community hardship and became a global test of endurance. That continuity—from a 45‑runner launch in 1983 to a multi-event summer series today—lives on in the race’s rules, its awards, and the way the town gathers to host athletes. For runners who love history, challenge, and altitude, Leadville is not just a race—you become part of a decades‑long tradition. Read the series history on the official site and the deep dive at iRunFar to feel that continuity.

If you’re dreaming about lining up in Leadville—bookmark this guide, study the official event pages now, and start building altitude‑specific fitness. The Race Across the Sky is waiting.

Quick links (bookmark this!)

• Official Leadville Trail 100 Run event page: LT100 Run event page
• Official Leadville Trail 100 MTB event page: LT100 MTB event page
• Leadville Race Series history: Leadville history
• Deep feature on the race’s founders and growth: iRunFar feature
• Historical winners and records (comprehensive): Leadville Trail 100 on Wikipedia and Leadville Trail 100 MTB on Wikipedia

Call to action

Ready to chase Leadville? Start with the official event page for the race you want, enter the lottery or qualify, and build a 12–16 week altitude‑specific block. If you want help planning your training or crew strategy for race week, share this guide with your crew and bookmark these official pages now—then start the climb.