park in southwestern Alberta, Canada, on the eastern slopes of the Rocky Mountains, immediately north of the U.S. border and Glacier National Park in Montana. It has an area of 203 square miles (525 square km). Established in 1895, it became a part of the Waterton-Glacier International Peace Park in 1932.

The terrain follows the transition from prairie grasslands to rugged, wind-swept peaks that rise to more than 9,000 feet (2,750 m). The slopes and valleys are coloured by a profusion of wildflowers and by forests of spruce, fir, and aspen. The grasslands and alpine meadows provide excellent habitats for black and grizzly bears, elk, mule, white-tailed deer, antelope, cougars, and coyotes. The high mountains are home to goats and bighorn sheep. Waterton Lakes, fed by the Waterton River and several brooks, are an important resting point for migratory waterfowl.