Ten kilometers west of Okotoks on Highway 7 is the Big Rock. It is the largest of the foothills erratics train, a series of boulders stretching over 700 kilometres along the eastern foothills of the Rocky Mountains from Jasper to Montana. This enormous quartzite block near Okotoks weighs about 16,500 tonnes. Geologists attribute natural processes as to why the Big Rock has split, however, a Blackfoot legend tells a different story, which can be discovered at the site.
The Big Rock has served as a landmark for native people and early pioneers. More recently it has attracted tourists and picnickers. In the 1970s, the Big Rock was the first “natural feature” to be designated as an official provincial historic site. The site and parking lot was officially opened year-round in early 2015. Parking and an interpretive sign are located on site.