Wildfires Threaten Summer Ultrarunning Events — image accompanying Marathon Handbook's report. Image accompanying Marathon Handbook’s report; reduced and presented for news commentary with the attributed report. View the complete source report.
Summer ultrarunning events face disruptions due to wildfires. Races like the Fat Dog 120 and Ouray 100 were canceled due to fires. Organizers cite safety risks and air quality concerns.
The demand for ultrarunning is growing, with 50,220 runners in 2025. However, wildfires are becoming more frequent and severe. The Hardrock 100 uses air-quality standards to decide race continuation. Read more trail coverage.
Forecasters predict a severe fire season. The sport faces a challenge in maintaining its summer calendar. Organizers adapt by rerouting courses and adding safety clauses, but cancellations impact runners and organizers. Related: Boréalys Mont-Tremblant by UTMB set for inaugural race weekend.
This original Runner World brief is based on reporting from Marathon Handbook. Visit the source for its complete reporting, context and any later corrections.
Reader questions
Questions about this report
What should runners know about Wildfires Threaten Summer Ultrarunning Events?
Increasing wildfires disrupt ultrarunning schedules in North America. Summer ultrarunning events face disruptions due to wildfires. Races like the Fat Dog 120 and Ouray 100 were canceled due to fires. Organizers cite safety risks and air quality concerns.
When did Runner World publish this trail brief?
Runner World published this brief on August 14, 2026. The underlying Marathon Handbook report was dated August 13, 2026.
Where can readers find the complete original report?
This summary is based on reporting from Marathon Handbook. The attributed source link in the article leads to the publisher’s complete report.
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