Sundance Mountain, also known as the Temple of the Sioux, rises in the southwest as part of the Bear Lodge Mountain Range that defines the northwestern edge of the Black Hills. Named for the Plains Indians' religious ceremony, it in turn gave its name to the town at its base and to the "Sundance Kid," one of that town's earliest and most notorious prisoners. In the Lakota language the mountain is called Wi Wacipi Paha, meaning Sun Dance Mountain, and some historians believe it was the site of the first sun dance hundreds of years ago. The Black Hills rise from the surrounding Great Plains prairies, where bison grazed, and provided Plains Indians with wood, water, berries, shade, stone, minerals, and smaller prey; they remain culturally important and contain many sacred sites. Covering 100 miles by 50 miles across the Wyoming-South Dakota border, the Black Hills are a geologic dome or uplift formed 80 million years ago during the Laramide Orogeny, when Precambrian stone buried miles underground was pushed to the earth's surface and softer upper sedimentary layers later eroded away to expose an ancient granite core ringed by progressively younger stone. Around that granite core lie the Madison limestone plateau, Red Valley, Dakota Hogback ridge, and an outer northern mountain belt. Red Valley, also called Redwater Valley, Red Beds, and Red Racetrack, takes one of its names from a Lakota account of a great running contest that caused the Black Hills to rise, spilling blood and staining the ground red. The area's colorful 200-300 million-year-old clays and shales erode easily into gullies and buttes, and bright white gypsum deposits dissolve still faster, leaving voids that collapse into sinkholes such as the Vore Buffalo Hunt. The northern outer ring includes nearby Sundance Mountain and the Bear Lodge Mountains to the west, the Black Buttes and Inyan Kara Mountain to the south, and Devils Tower and the Missouri Buttes to the northwest. Unlike the central peaks, these igneous mountains formed 53-55 million years ago as intrusions or laccoliths, when lava pressed upward between older rock layers and was later exposed by erosion; several of these peaks hold places in Lakota cosmology and religious practice.