2017 - 2018 North America Ultramarathon Calendar in May

Browse our Ultramarathon Calendar for races organized in North America during the month of May among 144 races.

144 races

Greenland Trail 50k

May 05, 2018 Race day in 9 months
USA / Mountain Region / Colorado / Larkspur
Ultramarathon
Trail Fast

Ragnar Trail Kentuckiana-KY, Presented by Salomon

May 11, 2018 Race day in 9 months
USA / East South Central / Kentucky / Brandenburg
Ultramarathon
Trail

Ragnar Trail Zion- UT, Presented by Salomon

May 11, 2018 Race day in 9 months
USA / Mountain Region / Utah / Mount Carmel
Ultramarathon
Trail

Glacier Ridge Trail Ultramarathon

May 12, 2018 Race day in 9 months
USA / Mid-Atlantic / Pennsylvania / Moraine State Park
Ultramarathon
Hilly Trail Relay

Glacier Ridge Trail Ultramarathon

May 12, 2018 Race day in 9 months
USA / Mid-Atlantic / Pennsylvania / Moraine State Park
Ultramarathon
Hilly Trail

Glacier Ridge Trail Ultramarathon

May 12, 2018 Race day in 9 months
USA / Mid-Atlantic / Pennsylvania / Moraine State Park
Ultramarathon
Hilly Trail

Knock on Wood

May 18, 2018 Race day in 9 months
USA / South Atlantic / South Carolina / Greenville
Ultramarathon
Trail

Keys 100

May 19, 2018 Race day in 9 months
USA / South Atlantic / Florida / Key Largo
Ultramarathon
Charity Relay

Keys 100

May 19, 2018 Race day in 9 months
USA / South Atlantic / Florida / Key Largo
Ultramarathon

Keys 100

May 19, 2018 Race day in 9 months
USA / South Atlantic / Florida / Key Largo
Ultramarathon
Relay

Scotiabank Calgary Marathon

May 27, 2018 Race day in 9 months
Canada / Alberta / Calgary
Ultramarathon
Charity Road Running

Scotiabank Calgary Marathon

May 27, 2018 Race day in 9 months
Canada / Alberta / Calgary
Ultramarathon
Charity Road Running Relay
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