Mount Timpanogos, often referred to as Timp, is the second-highest mountain in Utah's Wasatch Range. Timpanogos rises to an elevation of above sea level in the Uinta-Wasatch-Cache National Forest. With of topographic prominence, Timpanogos is the 47th-most prominent mountain in the contiguous United States. The mountain towers about over Utah Valley, including the cities of Lehi, Provo, Orem, Pleasant Grove, American Fork, Lindon and others. The exposed massif of the mountain is made up entirely of limestone and dolomite from the Pennsylvanian period, and is about 300 million years old. Heavy winter snowfall is characteristic of this portion of the Wasatch Range, and avalanche activity is common in winter and spring. The mountain is also home to Timpanogos Cave National Monument, a series of decorated caves in the north end of the mountain that have guided ranger tours open daily to the public during the warmer months. Etymology The word Timpanogos comes from the Timpanogots tribe who lived in the surrounding valleys from AD 1400. The name translates as "rock" (tumpi-), and "water mouth" or "canyon" (panogos). Glacial activity Mount Timpanogos displays many examples of various glacial processes and the sculpting power of moving ice. Ice Age glaciers mantled the peak until relatively recently and dramatically shaped the mountain into an Alpine tableau of knife-edge ridges and yawning, U-shaped amphitheaters. A remnant of these glaciers persists in the deeply recessed hanging valley below the main summit. Timpanogos Glacier is a rock-covered mass found on a long, north-facing slope and usually has patches of snow the entire year. Although an above-ground cirque glacier was present before the Dust Bowl Drought of the 1930s, no glacial ice is visible today. However, in 1994, a large crevasse opened up, revealing that there still is a glacier buried beneath the talus. Flowing water can occasionally be heard beneath the rocks. Emerald Lake, a small proglacial lake at the bottom of the cirque, often exhibits a blue color, indicating that the glacier is probably still moving, although perhaps too slowly to be noticeable. The locally unique ice is a relic of the region's formerly colder climate and has long been a major attraction to hikers and climbers on the mountain, who often slide down its permanent snowfield as a shorter descent route. Its precise classification remains the subject of ongoing debate, whether "real" or not. Hiking Mount Timpanogos is one of Utah's most popular hiking/climbing