Costa Rica does have street signs and streets with names and a logical system. Calles (streets) run one direction and Avenidas (avenues) run the other. But the Costa Ricans don’t use the system for the most part. Addresses really work like this: there’s some local landmark that everyone knows (it doesn’t even have to be there anymore) then you are so many meters north, so many meters west, and so many meters south of that place. So it might be like “Pan Am building, 600 m south, 300 m west, 20 m north.” And it works! Cab drivers will drop you off right at the door with this system and that’s how their addresses work for mail as well.
Inefficient and unwieldy, though.
Like going to my cousins place in Marietta, Georgia. Go past the big chicken and make a left.