Before there were cars, America’s country roads were unpaved, and they were abysmal. Back then, roads were so unreliable for travelers that most state maps didn’t even show them. This all started to change when early cyclists came together to transform some U.S. travel routes, and lay the groundwork for the interstate highways we use today.

Through the 1880s, spring and fall rains routinely turned dirt lanes into impassable mud pits that brought rural life to a standstill, stranding farmers …