Contained within the 4th Edition (1974) of the Atlas of Canada is a plate map that shows 2 maps. The first map shows the locations of airports and aerodromes as of 1967, and also time zone boundaries. Airports and aerodromes are denoted as being an international airport, a Department of National Defense aerodrome or other airport / aerodrome and as having precision approach capability, non precision approach capability or no approach instrumentation. The length of each airport or aerodrome's runway is also indicated. The second map, at a scale of 1:35 000 000, shows the locations of water aerodromes and heliports for all of Canada.