Gatineau (găt´Ĭnō), river, c.240 mi (390 km) long, rising in the Laurentians, SW Que., Canada, and flowing S to the Ottawa River at Hull. There are several rapids with hydroelectric power plants on the river.

Gatineau (găt´Ĭnō), city (1991 pop. 92,284), SW Que, Canada, at the junction of the Gatineau and Ottawa rivers, adjoining Hull. The fifth largest city in Quebec, it was created through the merger of 7 municipalities. Its diversified industrial base has led to rapid growth and extensive development since the mid-1970s.