Hill & Tibbit Super Service Station, Washington, D.C., 1934

By 1920, gasoline retailers determined that "island" gas pumps, which drivers could approach from either side, provided the most efficient station layout. They also realized that profits weren't made on the gasoline itself. Retailers instead made money by servicing and repairing cars, or by offering amenities like the "auto laundry" car wash at this station in Washington, D.C.