Some believe that the city earned its colors initially from Brahmins attempting to denote their caste (Brahmins, the priests and teachers, are the highest ranking members in the India's society dividing caste system) by painting their houses blue. The current widely believed reasoning is that indigo was added to the standard whitewash applied on houses to protect buildings from termites and other insects. Either way, the color scheme caught on and was adopted throughout the city, including buildings outside the city walls.