books.google.ca - The Plains region that stretches from northern Colorado to southern Alberta and from the Rockies to the western Dakotas is the land of the Cheyenne and the Blackfeet, the Crow and the Sioux. Its rolling grasslands and river valleys have nurtured human cultures for thousands of years. On cave walls, glacial...http://books.google.ca/books/about/Plains_Indians_Rock_Art.html?id=doUNbovdbogC&utm_source=gb-gplus-sharePlains Indians Rock Art
