There were more than two million finishers of half marathons in the U.S. in 2014—the most in history, according to Running USA's Annual Half Marathon Report. That makes the 13.1-mile distance the fastest growing in the sport, and the second most popular behind the 5K, which had more than eight million finishers last year. Here's how the half has changed over the past 25 years.
Correction: A previous version of this article stated that more than two million Americans finished a half marathon in 2014. The article has been corrected to say that there were more than two million finishers of half marathons in the U.S. in 2014.
