They loved visiting DSM when we lived there.Do the in laws also not like to go to Des Moines because its the "big city" and are afraid of the traffic?
My parents live in BFE rural iowa and for DECADES their address was Rural Route 2, xxxxxxx IA. Everything got delivered fine. Now with 911 address it still works but now you can put the address in maps and actually find it.
They’re late 60’s/early 70’s. Standard era Boomers