When I was younger, I used to think that "marathon" just mean any long race, or long thing. I had my main exposure to marathons by way of midnight movie marathons at the cinema. I have a very vague impression of marathons at school - though knowing primary schools they probably just called two laps of the oval a marathon for the athletics carnival.
A few years ago I found out that a marathon is actually a race of a specific length. Forty two point one nine five kilometers to be exact. And a few days ago I was watching some random YouTube videos and saw one of a dude that ran a marathon for his 42nd birthday.
So of course I thought - hey, I should do that! I can already run (okay, jog) 10km in about an hour, so allowing for slowing down over time I ought to be able to cover 40km or so in about six hours. An average adult can do it in five hours, four with a bit of training.
Then I remembered - I'm already over 42.
Dang.