Why Canadian airports start with a Y

Have you ever looked at the Canadian airport codes and thought why do they start with a Y and why don't they match the city like most other airports around the world do?

We know that the Canadian airport ICAO (International Civil Aviation Organization) code is "C" to identify the country in international aviation, with 'C' standing for Canada. 

For example, Toronto is CYYZ, Vancouver is CYVR, and Montreal is CYUL.

But have you ever wondered why the Canadian airport codes IATA (International Air Transport Association) codes start with "Y"?

Well, this is because in the 1930s and 40s, it indicated that a weather station or radio station was located on-site, with the "Y" standing for "Yes".

When three-letter codes were standardized, Canada added this "Y" to their existing two-letter radio or railway codes to identify that the airport was Canadian.

While rare, some Canadian airports still start with W, X, or Z, for example ZBF for Bathurst

 
Key details regarding the "Y" prefix:

Weather/Radio Station Indicator: The Y was used to show that an airport had a co-located weather station. If it did not have a station, a "W" (without) was used, though most adopted the Y.

Legacy from Rail/Telegraph: The two letters following the "Y" were often based on existing railway/telegraph station codes (e.g., YYC for Calgary, where "YC" was the original code)
.
Examples: YUL (Montréal), YVR (Vancouver), and YYZ (Toronto) follow this structure.

Here's how major Canadian airport codes
came to be:

• YYZ - Toronto -from old Malton railway telegraph code YZ
• YUL - Montréal-from the Kirkland radio / beacon code UL
• YOW- Ottawa-from early telegraph / aviation code OW
• YVR- Vancouver -Y + local Vancouver radio identifier
• YYC - Calgary - Y + local regional identifier derived from Calgary
• YEG - Edmonton-Y + Edmonton government / airfield identifier EG
• YWG - Winnipeg-Y + WG (Winnipeg government/ radio code)
• YHZ - Halifax -from local station / beacon letters HZ
• YQT - Thunder Bay - from old telegraph / field code QT
• YYJ - Victoria (Inner Harbour)-based on older station code YJ (James Bay area)
• YXE - Saskatoon - from historic radio / telegraph letters XE
• YQR - Regina - from earlier radio code QR
• YQB- Québec City - from local beacon telegraph QB
• YAM - Sault Ste. Marie - from old station code AM
• YZF - Yellowknife-from local field code ZF
• YXS - Prince George -- from older station code XS

But, just to confuse you a little more, here in Australia, all Australian airports are assigned an ICAO code beginning with "Y", because "Y" is the designated prefix for Australia.

A system that replaced older telecommunication codes where "Y" often signified a linked station, with the second letter indicating the Flight Information Region (FIR) like 'S' for Sydney YSSY, 'M' for Melbourne YMML and B for Brisbane YBBN.