When nature calls, look for signs that say "servicios sanitarios" or simply "sanitarios." In smaller venues, toilet paper is tossed into a trash bin rather than into the toilet. Septic systems are delicate and the paper will clog the toilet. At some public restrooms you might have to pay 50¢ or so for a few sheets of toilet paper. At others, there may not be any toilet paper at all. It's always a good idea to have some tissues at the ready. Gas stations generally have facilities, but you may decide not to be a slave to your bladder once you get a look at them. On car trips, watch for parked buses; generally this indicates some sort of better-kept public facilities.