What distances are considered ultramarathons?

Any footrace longer than 26.2 miles (42.2 km) is an ultramarathon. Common distances are 50K (31 miles), 50 miles, 100K (62 miles), and 100 miles. Some events are also measured by time — 12-hour, 24-hour, and 48-hour formats.

How do I register for an ultramarathon?

Most ultramarathons use Ultrasignup, iRunFar, or their own race websites for registration. Lottery-based races like Western States 100 and Hardrock 100 require submitting an entry during a specific window, often months in advance. Check each race's page for specific registration dates and qualifying requirements.

What should I look for when choosing my first ultramarathon?

For a first ultra, prioritize a 50K on moderate terrain with generous cutoff times. Look for a race with well-stocked aid stations every 5–8 miles. Avoid high-altitude or very technical courses until you have a 50K finish under your belt.

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