Inyan Kara Mountain, an isolated peak in northeastern Wyoming on the edge of the Black Hills, is important for its physical prominence, Lakota sacred meaning, and place in regional history. Known to the Lakota as Íŋyaŋ Káǧa, or Rock Gatherer, it is closely tied to Oceti Sakowin belief, the sacred power of stone, and the Stone Boy tradition linking the mountain to birth, healing, and purification through the Inipi ceremony. It was also known for unexplained rumbling sounds reported until 1833. George Armstrong Custer climbed it during the 1874 Black Hills Expedition, which helped spur the gold rush and intensify conflict that led to the 1876 military campaigns.