Rothrock by UTMB
May 14, 2027State College, PA50K, 20K
50K, 8 weeks before race day, 31 mi away, registration open
Ironstone 100K Ultra
Hollidaysburg, PennsylvaniaEastern States Trail-Endurance Alliance
- Entry
- $175
- Days to register
- 252
At a glance
- Date
- Jul 10, 2027
- Location
- Hollidaysburg, Pennsylvania
- Distances
- 100K
- Registration
- Closes Jul 1, 2027, via ultrasignup.com
Listed from UltraSignup. Checked Oct 18, 2026.
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Build my planAbout this race
Ironstone 100K is a savage point-to-point 100 kilometer ultramarathon on the wildest trails in the Ridge and Valley region of Pennsylvania, starting at Canoe Creek State Park in Blair County and ending at Greenwood Furnace State Park in Huntingdon County. The race features unforgiving technical terrain, ridge running atop Tussey Mountain, old-growth pines, and a 23-hour time limit.
Key dates
Registration closes
Jul 1, 2027
Race day
Jul 10, 2027
Pricing
Current price
$175
Registration
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Tune-up races
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May 15, 2027Lock Haven, PA47K, 25K +1
50K, 8 weeks before race day, 62 mi away
Straight-line distance
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July Races Nearby
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Race planning
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