Points within the city that are known to the local population are used as a reference for a particular address. Example: the address given to you to the particular place you want to go is 300 meters (or three blocks) from the southwest comer of the Cathedral and 150 meters (1-1½block) to the east, yellow house with white window bars. Or you might give the same address by calles and avenidas though you still must indicate that the house is yellow and has white window bars.
The problem arises when the owner of the house changes its colours or when a well known tree given as a reference point is cut down. The large centenarian higuerón tree, which was located at the entrance of the Los Yoses residential district, was cut down in the 1970s and many people still give it as a reference point.
During the 1940s through 1960s there was a beautiful obelisk in the centre of the Paseo Colón. It was an important reference point. Though demolished to make more room for traffic, many persons who remembered it still give it as a reference point. In this case they would say that such and such a place is so many meters or blocks from el old obelisk (the place where the old obelisk used to be). The new expatriate will at first find all this confusing, but in time he'll be as afilado (sharp) as a Tico.