From the World Heritage inscription:
In south-west Alberta, the remains of marked trails and an aboriginal camp, and a tumulus where vast quantities of buffalo (American Bison) skeletons can still be found, are evidence of a custom practised by aboriginal peoples of the North American plains for nearly 6,000 years. Using their excellent knowledge of the topography and of buffalo behaviour, they killed their prey by chasing them over a precipice; the carcasses were later carved up in the camp below.
I didn’t know what to expect when I visited this site, but in the end it was far more interesting than I thought it would be. Most people have an image of Indians on horseback hunting buffalo. Horses, however, weren’t introduced to the Americas until the arrival of the Europeans. Before that they had to walk everywhere. One of the easiest ways to hunt would be to heard bison into a group and run them off a cliff. Most of the tribe would be wait below the cliff to skin and process the bison that jumped. It was actually quite brilliant and very efficient way of providing food.