I was about to mention what I heard many years ago about 1 mile in every 5 of US highways having to be straight, so that in emergencies it could be used as a runway, but I decided to google it first for a reference and it turns out it's an urban legend: https://www.fhwa.dot.gov/publications/publicroads/00mayjun/o...

also some additional details here: https://science.howstuffworks.com/engineering/civil/were-u-s...