Some states (e.g., Indiana) have grids similar to the Interstate and US routes. Others have different systems: in Florida the first digit tells you roughly wher

Some states (e.g., Indiana) have grids similar to the Interstate and US routes. Others have different systems: in Florida the first digit tells you roughly where in the state it is, from 1xx routes in the Panhandle to 9xx routes around Miami. And still others just assigned numbers in order of construction, so on a map it makes no sense at all.