Blanca Peak, at 14,351 feet in southern Colorado, is the fourth-highest summit in the state and the highest point of the Sierra Blanca Massif, the Sangre de Cristo Range, and the Rio Grande drainage basin. Rising nearly 7,000 feet above the San Luis Valley in just 6 miles, it stands out for its dramatic relief and prominence. The mountain holds deep cultural importance for the Navajo as Sisnaajiní, the Sacred Mountain of the East, and it also bears names in other Indigenous languages. Its 1.8-billion-year-old granite, former glaciers, and recorded 1874 ascent add geological and historical significance to one of Colorado’s best-known fourteeners.