Metricated speed limit sign in Bolton, Ontario

“In April 1975 Fahrenheit temperatures were replaced by Celsius. In September 1975 rainfall was first measured in millimetres and snow in centimetres. Since April 1976, wind speed, visibility, and atmospheric pressure have been in SI units, with the pressure in kilopascals. In September 1977 every speed-limit sign in the country was changed from miles per hour to kilometres per hour.”