The design and performance of an ancient passively cooled mahal (building) have been presented. The mahal was generally used for pilgrims during their visit to the city of Banaras. Energy balance equations for different components, namely walls and roof, of a mahal have been used to evaluate the performance of the mahal in terms of an enclosed-room air temperature. It is observed that a reasonable thermal comfort temperature is achieved by ventilation using natural cold air through the windows.