Water is confined to scattered oases and sulfurous hot springs. Any city or town located at one of these few spots has a booming tourist industry. Intercontinental law provides that individuals are free to fill one container, once a day at any water source in the land, provided they can carry the container unassisted from the water source to the city gate. Special rates have been negotiated for the sale of water to other cities and territories in the land. Since in all of remembered time the oases have never dried up, cities are free to sell their water in any quantity and at any price they wish to businesses and other private establishments.