Castle Provincial Park, Nature reserve in Municipal District of Pincher Creek, Canada

Castle Provincial Park covers 25,501 hectares in the Municipal District of Pincher Creek No. 9, southern Alberta, sharing a boundary with Castle Wildland Provincial Park to the west and south. Its name comes from Windsor Ridge and the West and South Castle Rivers, which flow through the park. The terrain runs from subalpine forest to tundra, with short summers and long, snowy winters.

The region gained formal protection in 1908 when it became part of the Rocky Mountain Forest Reserve under the Dominion Lands Acts. This early designation established the foundation for long-term conservation of the area.

The Kutenai and Piikani First Nations called the area "A'saani", meaning sacred paint, and used it for spiritual ceremonies, hunting, food gathering and firewood collection for over 10,000 years. They later guided early explorers and traders through the Castle region.

The park maintains four campgrounds and multiple staging areas with various overnight options for different preferences. Trails for hiking, biking, and horseback riding are available throughout the year.

The park's name comes from Windsor Ridge and the West and South Castle rivers, not from a castle. The ridge itself was named Castle Mountain by geologist James Hector around 1861 and only renamed Windsor Ridge in 1979, when Mount Eisenhower in Banff became Castle Mountain.