The Black Hills of South Dakota are frequently referred to as an “Island in the Plains” and the description is an apt one. The Cheyenne River sets the southern border while the Belle Fouche River (pronounced Bell Foosh) defines the northern edge. To the west the Thunder Basin Grasslands of Wyoming and to the east the Buffalo Gap National Grasslands complete the circle around the hills.

The hills rise over 3,000 feet above the plains, reaching their pinnacle of 7,242 feet at Harney Peak, the highest point in North America east of the Rocky Mountains. About two thirds of the hills are located within the confines of the Black Hills National Forest. The southern region is mixed-grass prairie. The north is lush with ponderosa pine and even the ridges of the rolling hills of the south sport pine silhouettes. Seen from a distance, the deep green trees appear as a dark band on the horizon, giving the area its name.

From east to west about two-thirds of the hills are located in South Dakota and one-third spills into Wyoming. Several small rivers cut through the hills, most notably Spearfish Creek in the north, Rapid Creek in the central region, and Fall River in the south, and bring additional recreational and scenic beauty to the area.