Sandy Glacier is an alpine glacier on the west slope of Mount Hood in Oregon within the Mount Hood Wilderness. A remnant of the much larger ice masses left from the last ice age, it descends from about 8,800 feet to about 6,000 feet and feeds Muddy Fork, a tributary of the Sandy River. It is bounded by Yocum Ridge on the south and a ridge toward Glisan Glacier on the north. Its upper reaches have extensive crevasses, and its lower end once featured the Sandy Glacier Caves, possibly the largest glacier cave system in the lower 48 states. From 1907 to 2004, the glacier shrank markedly in area and length.