Snow cornice Snow cornice A snow cornice or simply cornice (from the Italian cornice meaning "ledge") is an overhanging edge of snow on a ridge or the crest of a mountain and along the sides of gullies. They form by wind blowing snow over sharp terrain breaks (e.g. the crest of the mountain) where it attaches and builds out horizontally. This build-up is most common on the steeper and leeward sides of mountains. Cornices are extremely dangerous and travelling above or below them should be avoided. When a cornice "collapses", it breaks in from the cornice to the top of the peak;
Mutter's Ridge and abandoned bases along the ridge to support operations against the PAVN, including Landing Zone Mack on Hill 484, Landing Zone Margo and Landing Zone Sierra. Mutter's Ridge Mutter's Ridge was the name given by U.S. Marines to the Núi Cây Tre ("Bamboo Mountain") ridge, in Quảng Trị Province. The ridge was formed by Hills 461, 484 and 400 and overlooked the southern edge of the Vietnamese Demilitarized Zone (DMZ) to the north and Route 9 to the south. The ridge was contested between the Marines and the People's Army of Vietnam (PAVN) starting with Operation Prairie in August 1966