Final answer:
The Black Hills is a western extension of the Rocky Mountains, which stretch from New Mexico to Canada. The Black Hills are known for their historical significance to the Sioux tribes and for landmarks like Mount Rushmore.
Step-by-step explanation:
The Black Hills is a western extension of the Rocky Mountains. The Rocky Mountains are a significant mountain range that extends from the southern United States in New Mexico, through Colorado, Wyoming, and Idaho, into northern Canada. The Black Hills in South Dakota are geographically considered part of the Rocky Mountains, and they are known for their rich history, including the discovery of gold and the ensuing conflicts between the United States government and the Sioux tribes, notably the Lakota. The Black Hills were considered sacred by the Indigenous people who lived there. The area has remained a point of cultural and political significance, exemplified by Mount Rushmore, which is carved into the granite of the Black Hills.