Lethbridge is a city in the province of Alberta, Canada. With a population of 101,482 in its 2019 municipal census, Lethbridge became the fourth Alberta city to surpass 100,000 people. The nearby Canadian Rocky Mountains contribute to the city's warm summers, mild winters, and windy climate. Lethbridge lies southeast of Calgary on the Oldman River. Lethbridge is the commercial, financial, transportation and industrial centre of southern Alberta.