How to change KM to Miles in Maps on MacBook Air

Thanks for a fast reply. I'm back to Miles which I appreciate. The part I don't understand, I never changed it to KM. If I had, I would certainly remember how to change it back to Miles. The only explanation I can offer, we recently spent some time in Germany and I assume the Map App changed it automatically to KM when I searched some driving directions over there. The question remains though, since we've been back in the US for weeks, how come the Map App did not automatically change it back to Miles? Anyway, thanks again.