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2015 - 2016 USA Ultramarathon Calendar in May

Browse our Ultramarathon Calendar for races organized in USA during the month of May among 130 races.

130 races

Armstrong Redwoods 50K

  • North America | USA | California | Guerneville
  • Ultramarathon - 50 kilometers
  • May 02, 2015 - 08:30
  • Hilly Trail

Canyons 50K Trail Run

  • North America | USA | California | Foresthill
  • Ultramarathon - 50 kilometers
  • May 02, 2015 - 07:30
  • Trail Mountain

Collegiate Peaks 50M Trail Run

  • North America | USA | Mountain Region | Colorado | Buena Vista
  • Ultramarathon - 50 miles
  • May 02, 2015
  • Trail

Grand Ridge 50K Trail Run (May)

  • North America | USA | Pacific | Washington | Issaquah
  • Ultramarathon - 50 kilometers
  • May 02, 2015
  • Trail Evergreen Trail Runs

Greenland Trail 50k

  • North America | USA | Mountain Region | Colorado | Greenland
  • Ultramarathon - 50 kilometers
  • May 02, 2015 - 08:00
  • Trail

Labor of Love 100M

  • North America | USA | Mountain Region | Nevada | Lowell Canyon
  • Ultramarathon - 100 miles
  • May 02, 2015
  • Road Running Calico Racing

Labor of Love 50K

  • North America | USA | Mountain Region | Nevada | Lowell Canyon
  • Ultramarathon - 50 kilometers
  • May 02, 2015 - 06:00
  • Calico Racing

Labor of Love 50M

  • North America | USA | Mountain Region | Nevada | Lowell Canyon
  • Ultramarathon - 50 miles
  • May 02, 2015
  • Road Running Calico Racing

Me-Ow Quads

  • North America | USA | California | Whiskeytown
  • Ultramarathon - 104.8 miles
  • May 02, 2015
  • Charity Trail Shasta Trail Runs Mountain

Me-Ow Siamese

  • North America | USA | California | Whiskeytown
  • Ultramarathon - 42.4 miles
  • May 02, 2015 - 06:00
  • Charity Trail Shasta Trail Runs Mountain

Miwok 100K Trail Race

  • North America | USA | Pacific | California | Rodeo Lagoon
  • Ultramarathon - 100 kilometers
  • May 02, 2015 - 05:40
  • UTMB Qualifier Trail Western States Qualifier

Nirvana Ultra Big Bear 100K

  • North America | USA | California | San Bernardino National Forest
  • Ultramarathon - 100 kilometers
  • May 02, 2015 - 06:00
  • Trail Nirvana Racing Co. Ultra Marathons Mountain

Nirvana Ultra Big Bear 100 Mile

  • North America | USA | California | San Bernardino National Forest
  • Ultramarathon - 100 miles
  • May 02, 2015 - 06:00
  • Trail Nirvana Racing Co. Ultra Marathons Mountain

Nirvana Ultra Big Bear 50K

  • North America | USA | California | San Bernardino National Forest
  • Ultramarathon - 50 kilometers
  • May 02, 2015 - 06:00
  • Trail Nirvana Racing Co. Ultra Marathons Mountain

Nirvana Ultra Big Bear 50 Mile

  • North America | USA | California | San Bernardino National Forest
  • Ultramarathon - 50 miles
  • May 02, 2015 - 06:00
  • Trail Nirvana Racing Co. Ultra Marathons Mountain