At least once a year (especially before August 15, the Feast of the Dormition), you will see the women of Paros bent in front of their homes and shops repainting the whitewashed outlines of the streets’ dark flat stones. They trace those lines often created years and years before by their ancestors.
Actually, the paint used today is not whitewash but a synthetic varnish. Originally, whitewash was made of calcimine or lime. Because of its anti-bacterial properties, whitewashing streets was done mainly for reasons of sanitation. But today it’s done mainly for tradition and aesthetics.
No one is forced to do it. It’s an instinct that comes naturally if you have a sense of community. Everyone has their own style depending, in part, upon what kinds of street you have, what’s already been painted and how much paint you can afford.