What a vehicle carries on average is unrelated to its actual capacity. Regardless my point is you see a kei truck you’ll almost certainly see the bed packed full, you see a Sierra 2500 chances are it’s need is totally empty aside from oftentimes boots and beer cans.
You missed the craziest part, it started being dug in the time of ancient Greece and in fact there’s a commemoration carving of Hercules on one of the entrances.
https://corinthianmatters.org/2016/04/11/on-the-remains-of-neros-corinth-canal-project/