The year before the first US marathon was held in Boston in 1897, a Turkey Trot was held in upstate New York. The Buffalo Turkey Trot is now the oldest continuously-running race in North America and it has 14,000 participants, more than 2000 times the number it had its first year.
The local YMCA hosted an 8K cross-country race that Thanksgiving Day, drawing just six participants—and only four of them made it to the finish line. One runner excused himself after two miles; another dropped out when his "late breakfast refused to keep in its proper place." The winner, Henry A. Allison, crossed the line in 31 minutes and 12 seconds, averaging a six-minute-per-mile pace.
Despite its humble beginnings, the race was held again the next year, and the year after that, and the year after that. In fact, it's been held every single year since—even during the coronavirus pandemic, where they kept the in-person field to a meager 125 randomly-selected runners, one per year of the race's existence. This makes it the oldest continuous footrace in North America.
The Buffalo race inspired other Turkey Trots. In 2016, nearly one million people participated in Turkey Trot events before gobbling down Thanksgiving dinner.