PAINANI
PAINANI

PAINANI · RUN / LOCAL

32 · Arizona, USA

Javelina Jundred

Run the 31 km Sonoran desert loop that Javelina Jundred repeats five times for 100 miles: sandy washes, granite boulders, saguaros, one long climb, four aid stations.

Trail runningUltramarathonLoop
31.3 kmDistance355 mElevation gainHardSite gradeFountain HillsNearest base

Site grade

HardFeatured

A 31 km loop with 355 m of gain is runnable ground; what makes it hard is 10.5 km between water at Coyote Camp and Jackass Junction, a park that rates every trail one level harder in the hot months, and, for the race, repeating the loop five times through a night.

The experience

The loop itself is rolling single-track with 355 m of gain: sand in the washes, rock on the climb to Coyote Camp, smooth footing on the Pemberton descent. The race adds four repetitions, a Halloween-night lap in the dark, and a 30-hour clock.

It is the party ultra. The organizer calls it the original costumed 100-mile trail run and rates the event R; the aid station at Jackass Junction is the party and the 31K night race exists so people can visit it. It is also a Western States 100 qualifier and Golden Ticket race.

The Hohokam farmed and hunted across this ground from about AD 300 to 1450, and archaeological sites inside the park record their presence. Camp McDowell, the only army fort within present-day Maricopa County, stood on the Verde River a few miles southeast from 1865 to 1890. The county leased the first 18,273 acres of the park in 1958; it now covers 21,099 acres.

Where the sources disagreeAs of 16 September 2026 the 2026 100 mile is full: the field is capped at 1,000 runners, the organizer's page offers only a waitlist, and registration closes on 1 October 2026. Outside race weekend the loop is an ordinary multi-use park trail with no aid: $10 per vehicle at the gate, park open 5 am to 9 pm until 31 October and 6 am to 8 pm from 1 November, mountain bikes and horses on the same tread, and a park rule that rates every trail one level harder in the hot months. Dogs are allowed in the park on a 6 ft leash but banned anywhere on the race site.

Trail path

The line
you follow.

StartFour Peaks Staging Area (Javelina Jeadquarters), McDowell Mountain Regional ParkFinishFour Peaks Staging Area (Javelina Jeadquarters), McDowell Mountain Regional ParkDirectionOut through Shallmo Wash, north along the Pemberton Trail toward the McDowell Mountains, back via the Cinch Trail
  1. 01Four Peaks Staging Area
  2. 02Shallmo Wash
  3. 03McDowell Mountain Park Drive crossing
  4. 04Pemberton Wash
  5. 05Tonto Tank Trail junction
  6. 06Coyote Camp
  7. 07Granite Tank and Jackass Junction
  8. 08North Road crossing and Rattlesnake Ranch
  9. 09Cinch Trail
  10. 10Four Peaks Staging Area

Route sections

01 · Shallmo WashFour Peaks Staging Area to Coyote Camp
Sand first: the loop leaves through Shallmo Wash, crosses the park road, and rolls through Pemberton Wash before a sharp left at the foot of the long climb. Coyote Camp aid sits near a park service road at the top of the first ascent.02 · The Six and a HalfCoyote Camp to Jackass Junction
The longest gap between aid on the course, 6.5 miles (10.5 km). A rocky climb levels out and turns north toward the McDowell Mountains, then narrows through washes with erosion-control logs and 20 to 50 ft rises, past granite boulders, down to Granite Tank.03 · Pemberton DownhillJackass Junction to Rattlesnake Ranch
Gradual downhill single-track beside the old jeep road. The fastest running on the loop, and the stretch that tempts a 100-miler into a pace the fourth loop will collect on.04 · The CinchRattlesnake Ranch to Four Peaks Staging Area
Pemberton Trail to the short Cinch Trail and home. On loop one of the race this leg is the Escondido Trail instead, 6.6 miles with no aid, which is why loop one is 22.3 miles and the rest 19.45.

Weather profile

What the sky
is likely to do.

Low Sonoran desert at 500 to 760 m. Days on race weekend are warm and exposed, nights are cold enough that the organizer tells crews to bring layers. The park rates its trails one level harder when heat or humidity is high, and its annual fire ban runs 1 May to 30 September.

Season & timing

Managed seasonThe park is open year round: 5 am to 9 pm from 1 May to 31 October, 6 am to 8 pm from 1 November to 30 April.Best windowRace weekend if you hold an entry. For the loop alone, the cool half of the year, 1 November to 30 April, starting at the 6 am gate.Race timingJavelina Jundred: 31 October to 1 November 2026. 100 mile waves 6:00 and 6:30 am Saturday, 100K 7:00 am, Jackass 31K 6:00 pm Saturday. Final cutoff 12:30 pm Sunday.SurfaceDesert single-track: sandy wash, decomposed granite, rocky climb, erosion-control logs, one paved park road crossingDirectionOut through Shallmo Wash, north along the Pemberton Trail toward the McDowell Mountains, back via the Cinch Trail

Signature moments

What you will
remember afterwards.

01

Crossing McDowell Mountain Park Drive minutes after the start

02

The sharp left at the foot of the long climb to Coyote Camp

03

Granite boulders on the plateau before Jackass Junction

04

Saguaros beside the Pemberton Trail on the descent

05

The finish-line tent at Javelina Jeadquarters on a fifth pass

ENTRY LIMIT

1,000

Runners in the 100-mile field, all sharing one 19.45-mile loop

The organizer caps the 100 mile at 1,000 runners, the 100K at 500 and the 31K at 325, and the 2026 100 mile is already on a waitlist. Every one of them passes Javelina Jeadquarters on every lap, which is why crews never have to drive.

Access & logistics

AccessFrom central Phoenix take Loop 202 east to SR 87, then Shea Blvd west, Saguaro Blvd north through Fountain Hills, and Fountain Hills Blvd four miles to the park gate. The race starts from the Four Peaks Staging Area, 16300 McDowell Mountain Park Drive. On race day the gate opens at 4:00 am.PermitsNone for the loop. Park entry is $10 per vehicle or $5 per person on foot, bike or horse, payable at the gate; an annual county pass is $120. Race weekend is a permitted event: crewing only at Javelina Jeadquarters, camping only with a permit, no pets on site.BookingsRace entry via UltraSignup: $525 for the 100 mile, $375 for the 100K, $195 for the 31K in 2026, and the 2026 100 mile is waitlist only. Crew canopies ($100) and RV sites for 2026 are sold out. Park camping for other dates is reserved through Maricopa County Parks.WaterNone on the trail. In the race, four aid stations per loop: Javelina Jeadquarters, Coyote Camp, Jackass Junction and Rattlesnake Ranch, with 6.5 miles between Coyote Camp and Jackass Junction and the organizer's advice to carry two bottles from loop two. Outside the race, carry everything and turn around when half is gone.FoodRace aid stations serve gels, salt, fruit, broth, quesadillas, burritos and burgers at Jackass Junction; a drop bag can wait at Jackass Junction and at the start. Fountain Hills has groceries and restaurants ten minutes south of the gate.DurationNo land-manager time for the loop. The race allows 8.5 hours for one loop in the Jackass 31K and 30 hours for the five-loop 100 mile.

Key hazards

  • ▲Heat and sun on an exposed course
  • ▲Rattlesnakes
  • ▲10.5 km between aid stations, and none outside the race
  • ▲Mountain bikes and horses on a shared trail
  • ▲Sandy washes that drain the legs early
  • ▲Night running on the fourth and fifth loops
  • ▲Cold overnight temperatures in late October

SafetyOrientation only. Always use current official maps, alerts and safety guidance. Carry more water than you think, start at the gate opening in warm months, and tell someone your plan.

Check park updates →Request this run →

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Official sources

Last verified 2026-09-16 · Record CETC-RUN-032 · Orientation only. Always use current official maps, alerts and safety guidance.

Photograph: Andy Blackledge · CC BY 2.0