The Departamento de Canelones is one of the 19 Uruguayan departments. With an area of 4,536 km2 (1,751 sq mi) and 518,154 inhabitants, it is located in the south of Uruguay. Its capital is Canelones. Ciudad de la Costa is the largest city by total population and Las Piedras is the largest city with an official census.

Ciudad de la Costa is a city in Canelones Department of Uruguay, on the banks of the Río de la Plata between the streams Arroyo Carrasco and Arroyo Pando. It is considered an extension of the metropolitan area of Montevideo which it borders to the west, while to the east it borders Costa de Oro. It was declared a city on 19 October 1994 and given its current name. At the 2011 census, it was the second most populated city of Uruguay between Montevideo and Salto.