marathon distances - SERP Analysis

https://sports.yahoo.com/long-does-average-runner-complete-025956996.html

https://raceraves.com/distances/

https://en.wikipedia.org/wiki/Marathon

https://marathonhandbook.com/types-of-race/

https://therunningchannel.com/how-far-is-a-marathon/

https://stories.strava.com/articles/everything-you-need-to-know-about-running-a-marathon

https://www.reddit.com/r/Marathon_Training/comments/1cwwalg/why_is_a_marathon_such_a_weird_and_specific/

https://therunningchannel.com/distance-conversions-runners-miles-kilometres/

https://www.mccourtfoundation.org/event/los-angeles-marathon/distances-courses/

https://www.britannica.com/sports/marathon-race