Once Upon A Time, this guy run a really long way
He delivered a message about war or something
And promptly dropped dead.
Thousands of years later, a bunch of people thought it would be an awesome idea to repeat this incident every year all over the world. They caused lots of annoying traffic and disruptions and made it really hard for everyone to get to work.
[This shitty comic is dedicated to the poor souls who have tragically lost their lives running the marathon.]