If you’ve traveled throughout Colombia, you’ve surely come across the typical streets lined with houses which have a tendency to be painted two colors. This has a name (the lower section, at least) and it is called a zócalo and is probably an old custom imported from Spain as one can see the same style in the old houses there.
As to why it is done, the point behind it is to protect the houses from erosion in the case of the passage of rainwater through the streets. Up to 80 centimeters from the ground, the a coat of cement is used in order to do the job. Perhaps the paint, then, signifies the point to which the house is protected from being eroded.
In Guatapé, near the city of Medellín, the residents have made the zócalos into an art form by embedding designs in them. One could say that these designs tell a story of sorts, about the town and those who live in it. The zócalero profession has even emerged to meet the demand for such a service and they even compete amongst themselves to see who can design the best zócalo. No longer using only cement, there are those who make frescos (paintings set in plaster) to create more elaborate works.