How technical is Unbound XL?

Sharp Flint Hills limestone slices tires while you make constant line choices in darkness. The 2023 mud turned bikes immovable - Chris Mehlman went "eight miles in two-and-a-half hours" through Kansas clay that "resembles concrete" and clogs drivetrains in seconds.[1]

Unbound XL Review 2027 | Kansas

[01]

Course Overview

350 miles of Kansas limestone hell with zero aid stations. The ultimate test of whether you actually like riding bikes or just think you do.

350 mi

Distance

14,000 ft

Elevation

Emporia, Kansas

Location

Friday, June 4; final 2027 route and elevation are pending, 2027

Date

Field Size

$270

Entry Cost

+ Google Calendar Download .ics

MORE IN KANSAS: Unbound Gravel 200 · Unbound Gravel 100 · Belgian Waffle Ride Kansas

[03]

The Course

Aerial view of cyclists racing in formation on gravel road through Kansas farmland with green fields and rural landscape - Unbound XL - Emporia, Kansas

Close-up selfie of gravel cyclist in colorful EF kit with sunglasses and helmet racing on dirt road through rolling prairie landscape - Unbound XL - Emporia, Kansas

Unbound XL is a 350-mile commitment to Kansas limestone gravel that slices tires and punishes poor line choices across the rolling Flint Hills. The course feels like prairie purgatory — constant undulations that never let you settle into a rhythm, with long stretches between gas station salvation points. Sharp, chunky gravel demands constant vigilance while the relentless rollers chip away at your soul one hill at a time.

Signature challenge: The 75-mile gap between meaningful resupply points turns nutrition into a high-stakes chess match. Most riders crack not from the hills or the gravel, but from running out of food or water in the Kansas void where gas stations close at 10 PM and your mistakes compound in the darkness.

40

MILE

First Reality Check

Eskridge arrives right when the course diverges from the 200-mile route, marking your entry into true isolation. The limestone has already announced its intentions on your tires and legs.

110

MILE

The Northern Wasteland

Alma to Alta Vista represents the most remote section — 75 miles of Kansas nothingness with no resupply options. Your planning mistakes become apparent here, usually around 2 AM.

210

MILE

The Gravel Gauntlet

Past Council Grove, fatigue meets the course's most technical terrain. Every rock wants to end your race while your body starts the serious negotiations about quitting.

320

MILE

The Final Crucible

The last 30 miles back to Emporia feel longer than the previous 100. Your bike is destroyed, your body is broken, but the finish line finally becomes real.

RIDERS REPORT

Early race crashes MI 7-8

Multiple crashes happen very early in the race, around mile 7 or 8, often when riders aren't expecting it during lulls in racing.

Heat management MI 70

Heat becomes a major factor as the day progresses, causing groups to dwindle and wreaking havoc on power late in the race. This is described as the critical moment where people either crack completely or break into top positions.

Sharp rocks are a constant hazard on the course that riders must navigate.

The course features rolling terrain that becomes more challenging as heat builds throughout the day.

Different sections have distinct characteristics - some are famous for being really fast, others for causing non-stop punctures, and some for being real tough, gritty sections.

[04]

From the Field

The XL is a much more relaxed pace, we're still going fast we're still going hard but at 350 miles it's not very spicy but here's the main thing it's fully self-supported so when you stop to get food and water that's on your own dime you've got to stop at little grocery stores little markets.
VC Adventures · 360.9K views

I went out towards the mud marathon section from 2023 and 2015, and they didn't actually do that on the route, but I decided I was going to just ride off course a little bit, and it was completely dry. It was ridable.
Gravel Guru · 5.1K views

There's always a little bit of sadness, you know, inside because of what happened in 2023. But someday, someday, someday, I think I'll be on that start line again for the XL.
Gravel Guru · 5.1K views

For XL distance it's fully self-supported so when you stop to get food and water that's on your own dime you've got to stop at little grocery stores little markets you got to kind of plan that along the way
VC Adventures · 360.9K views

My First ULTRA Bike Race (Unbound XL - 350mi / 563km)

VC Adventures · 360.9K views · 43:24

Unbound Gravel XL Launch - Friday in Emporia!

Gravel Guru · 5.1K views · 4:08

[07]

Training

June 4, 2027 UNBOUND XL

RIDERS REPORT

For XL distance (350 miles), riders use suspension forks like the RockShox 35 ARS with 42mm double cross IRC tires filled with Orange Seal tubeless sealant.

Pro race setups use road-oriented gearing: 11-34 Dura Ace cassette with 34-50 chainrings, optimized for the crazy high speeds of the pro race.

Chain waxing is important - riders use products like Silca Endurance chip wax for the long distance.

[08]

Train for Unbound XL

RACE DEMAND PROFILE

Durability

10

Climbing

9

VO2 Power

10

Threshold

5

Technical

8

Heat

8

Altitude

4

Race Specificity

10

3 WORKOUTS BUILT FOR THIS RACE

Each workout below is selected from our archetype library based on Unbound XL’s specific demands. Click any workout to see the full execution protocol.

Durability Double Day Simulation

2hr (AM+PM) +

Two sessions in one day — AM endurance, PM intensity. Trains the double-day fatigue of multi-day events.

350 miles. Your legs will beg to quit after 120. This trains the power output you need from mile 130 onward.

AM: Z2 1hr

REST

PM WU

10m FTP

5m

10m FTP

CD

STRUCTURE AM: 1hr Zone 2 | PM: 10min warm-up → 2×10min @ 95% FTP / 5min recovery → cool-down

EXECUTION The AM ride loads fatigue. The PM session tests your ability to produce quality power on pre-stressed legs. This is what stage racing and back-to-back hard days feel like. Don’t skip the AM ride — that’s the whole point.

POWER AM: 65–70% FTP | PM intervals: 93–97% FTP | PM recovery: 55% FTP

CADENCE AM: 85–90rpm easy | PM: 85–95rpm on intervals

POSITION AM: comfortable, any position | PM: race position for intervals

RPE AM: 3–4 | PM intervals: 7–8

RACE-SPECIFIC: UNBOUND XL

HEAT PREP May in Emporia, Kansas. Begin heat acclimatization 10–14 days before Unbound XL — 20–30min sauna sessions or midday rides in full kit. Pre-load sodium 48 hours out. Target 500–750ml/hr with electrolytes on race day.

NUTRITION Ultra-distance fueling for 350 miles: 80–100g carbs/hour from mile 1 — don’t wait until you’re hungry. Practice your exact race-day nutrition in every long training ride. Carry backup calories. 350 miles burns 8,000–12,000+ calories — you cannot replace them all, but you must try.

ALTITUDE Moderate altitude at Unbound XL. Arrive 2–3 days early. Reduce intensity expectations by 5–10%. Hydrate aggressively.

TERRAIN Highly technical terrain at Unbound XL demands practice on similar surfaces. Ride pure limestone gravel — sharp edges regularly destroy tires, constant line-choice decisions at race-day cadence weekly. Practice cornering, descending, and power delivery on unstable surfaces. Dial in tire pressure before race week — 5 PSI wrong costs you 15+ minutes over 350 miles.

VO2max 5x3 VO2 Classic

1hr +

The gold standard VO2max session — 5 efforts at your aerobic ceiling.

14,000ft of climbing means repeated surges above threshold. VO2max work is how you survive the fifth climb, not just the first.

WU 10m

3m

CD

Endurance Terrain Simulation Z2

2hr +

Zone 2 with rolling terrain simulation — undulating power that builds fat oxidation.

Every hard session works better with a bigger aerobic base. At 350 miles, base fitness is the difference between racing and surviving.

WU

RISE

FLAT

RISE

VALLEY

RISE

FLAT

RISE

VALLEY

RISE

CD

STRUCTURE 10min warm-up → 1.75hr alternating 4min @ 72–78% FTP (rises) and 6min @ 62–68% FTP (valleys) → cool-down

EXECUTION Stay in Zone 2 the entire time, but undulate your power to simulate rolling terrain. The rises push the top of Z2; the valleys ease off. This builds terrain-responsive pacing without leaving the aerobic zone. Your body learns to modulate power without thinking.

POWER Rises: 72–78% FTP | Valleys: 62–68% FTP | All within Zone 2

CADENCE Rises: 80–85rpm | Valleys: 88–92rpm

POSITION Alternate: hoods on rises, drops on flats. Build position endurance.

RPE 3–4 throughout — never hard, but never mindless

RACE-SPECIFIC: UNBOUND XL

HEAT PREP May in Emporia, Kansas. Begin heat acclimatization 10–14 days before Unbound XL — 20–30min sauna sessions or midday rides in full kit. Pre-load sodium 48 hours out. Target 500–750ml/hr with electrolytes on race day.

NUTRITION Ultra-distance fueling for 350 miles: 80–100g carbs/hour from mile 1 — don’t wait until you’re hungry. Practice your exact race-day nutrition in every long training ride. Carry backup calories. 350 miles burns 8,000–12,000+ calories — you cannot replace them all, but you must try.

ALTITUDE Moderate altitude at Unbound XL. Arrive 2–3 days early. Reduce intensity expectations by 5–10%. Hydrate aggressively.

TERRAIN Highly technical terrain at Unbound XL demands practice on similar surfaces. Ride pure limestone gravel — sharp edges regularly destroy tires, constant line-choice decisions at race-day cadence weekly. Practice cornering, descending, and power delivery on unstable surfaces. Dial in tire pressure before race week — 5 PSI wrong costs you 15+ minutes over 350 miles.

FREE

GET THE UNBOUND XL PREP KIT

12-week training timeline, race-day checklists, packing list, and personalized fueling calculator — unlocked instantly.

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[10]

Tire Picks

45mmWET

1

Schwalbe G-One Overland

45mm · $70 · 40W

high puncture protection for sharp surfaces. excellent wet grip

2

Pirelli Cinturato Gravel S

45mm · $74

high puncture protection for sharp surfaces. excellent wet grip

3

Vittoria Terreno Wet

45mm · $80 · 39W

excellent wet grip

FULL TIRE GUIDE & PRESSURE TABLE

NEWS

Latest Coverage

[—]

Frequently Asked Questions

What is the climate like at Unbound XL?

Late May Kansas delivers 24+ hours of weather variability including 60 mph winds. Heather Jackson experienced "an hour of chaos" when her headlamp failed in darkness. Anne-Marije Rook found sunrise brought "heat and humidity" after looking forward to the "boost of energy that light usually provides."[2]

How are the logistics for Unbound XL?

Kansas City or Wichita airports are 1.5-2 hours away. Emporia hotels book fast and spike during race week. "Unbound Gravel temporarily increases the population of Emporia, Kansas by 50%." Small-town infrastructure gets overwhelmed by 12,000 visitors.[14]

How adventurous is Unbound XL?

Night riding through Flint Hills prairie creates otherworldly experiences. Anne-Marije Rook encountered "two cows headed straight toward me" at 4 AM after 13 hours in the saddle. Rob Britton found the adventure transformative: "The sunset was incredible, the sunrise was amazing. Riding through the night was amazing."[2]

How prestigious is Unbound XL?

The most prestigious ultra-distance gravel race in the world. The XL predates the ultra-gravel movement and set the template everyone else copies. Winning here puts your name in gravel history.[14]

Should I race Unbound XL?

You need to finish a 200-miler first, preferably two. The 36-hour cutoff sounds generous until you're grinding limestone in your 16th hour with 150 miles still ahead. Self-supported means what it says—no crew, no checkpoints, just you and whatever gas stations stay open past midnight in rural Kansas.

[11]

Sources & Citations

Research sources used to build this race profile. Always verify details with official race sources before making travel or registration decisions.

Route Maps RideWithGPS: XL - Garmin UNBOUND Gravel 2023ridewithgps.com/routes/53768538
Media & Press Velovelo.outsideonline.com/gravel/gravel-racing/rob-britton-a...
Media & Press Velovelo.outsideonline.com/gravel/the-hardest-part-about-raci...
Media & Press Velovelo.outsideonline.com/tag/unbound-gravel/
Media & Press BikeRadarwww.bikeradar.com/features/routes-and-rides/what-is-unbou...
Media & Press Cycling Weeklywww.cyclingweekly.com/gravel/rob-britton-smashes-350-mile...
Media & Press Cycling Weeklywww.cyclingweekly.com/news/gravel-riders-ready-here-are-t...
Media & Press Cycling Weeklywww.cyclingweekly.com/news/i-rode-the-352-mile-unbound-xl...
Community Redditwww.reddit.com/r/gravelcycling/comments/1d8qdg7/unbound_x...
Community Redditwww.reddit.com/r/gravelcycling/comments/v5fo78/aftermath_...
Community cyclingnews.com: Resultswww.cyclingnews.com/races/unbound-gravel-2025/unbound-xl-...
Community ridemaple.com: 2023 Unbound Gravel Xl Recapridemaple.com/blogs/news/2023-unbound-gravel-xl-recap
Community salsacycles.com: Surviving The Unbound Gravel Xl Tips From Past Finisherswww.salsacycles.com/blogs/articles/surviving-the-unbound-...
Official UNBOUND Gravel XL: 2027 date, distance, price, lottery, and formatwww.unboundgravel.com/events-xl/
Reference Wikipediaen.wikipedia.org/wiki/Unbound_Gravel
Live Tracking TrackLeaderstrackleaders.com/unboundxl24
Other Sources Bikerumorbikerumor.com/unbound-gravel-200-xl-2023-results/
Other Sources Blogblog.otsocycles.com/2024/08/support-through-the-unsupport...
Other Sources Escapecollectiveescapecollective.com/gallery-and-report-britton-jackson-w...
Official UNBOUND Gravel: current official ruleswww.unboundgravel.com/officialrules/

Unbound XL

The Ratings

Train for Unbound XL

Course Overview

The Course

From the Field

Racer Reviews

RATE UNBOUND XL

Training

Train for Unbound XL

RACE DEMAND PROFILE

3 WORKOUTS BUILT FOR THIS RACE

GET THE UNBOUND XL PREP KIT

Tire Picks

Latest Coverage

Similar Races

Frequently Asked Questions

What is the climate like at Unbound XL?

How are the logistics for Unbound XL?

How adventurous is Unbound XL?

How prestigious is Unbound XL?

Should I race Unbound XL?

Sources & Citations