Contained within the 3rd Edition (1957) of the Atlas of Canada is a map that shows the locations of civil airports and aerodromes up to September 1957, together with the operational type of airport or aerodrome. The airports were classified according to class of Air Carrier each is technically and administratively equipped to serve. Major Airports are those equipped to service all classes of Air Carrier; Other Scheduled Airports are those equipped to service all classes of Air Carrier, except International Scheduled Air Carriers; Non-scheduled Airports can service one or more of the all classes, except Scheduled Air Carriers and International Scheduled Air Carriers; Water Airports shown are all Non-scheduled Airports. The map showing these airports also includes Canadian time zones circa 1957.