It's unimaginable today to have a New York City Marathon with little fanfare and virtually no media coverage, but that's exactly how the inaugural race played out on Sept. 13, 1970.
The course was confined to Central Park and the field was only 127 runners.
Only 55 of them would finish that day - including the winner Gary Muhrcke - who had signed up just 15 minutes before the race.
In 1972, six female competitors took a stand by staging a sit-in on the starting line to protest rules prohibiting men and women from running together.
The iconic moment helped put the sexes on equal footing.
It wasn't until 1976 that the NYC Marathon expanded to a five-borough race. It became the first 'city streets marathon' - a move that not only changed the course of the race, it changed the course of the sport.
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Over the decades, crowds lining the marathon course grew into the millions and the NYC Marathon became the biggest in the world.
2020 isn't the only year the Marathon was called off - it was also canceled in 2012 in the wake of Superstorm Sandy.
But in the fall of 2001, after the 9/11 attacks, the Marathon went on and helped to lift New Yorkers out of their collective grief.
The NYC Marathon has turned some elite runners into legends, including 9-time winner Grete Waitz, 4-time winner Bill Rodgers and 5-time winner in the women's wheelchair division, Tatyana McFadden.
In 2009, Meb Keflezighi became the first American to win since 1982. And in 2017, Shalane Flanagan became the first American woman to win in 40 years.
New York Road Runners race director Jim Heim said more than 1.8 million people have crossed over the finish line and they look forward to adding to that number in 2021.
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