Waterloo is a city in Southern Ontario, Canada. It is the smallest of the three cities in the Regional Municipality of Waterloo (and previously in Waterloo County, Ontario), and is adjacent to the city of Kitchener.
Kitchener and Waterloo are often jointly referred to as "Kitchener-Waterloo", "KW", the "Twin Cities" or "the Tri-City". (When the reference includes the city of Cambridge, Ontario, the term Tri-Cities is used.) Years ago, there had been several attempts to combine the two cities into one but they were not successful. After 1973, when the Regional government was formed, there was less motivation to do so. At the time of the 2016 census, the population of Waterloo was 104,986.
In 2016, MoneySense rated Waterloo as the tenth best place to live in Canada.