Avalanche Glacier lies on the west to southwest slopes of Mount Adams in Washington’s Gifford Pinchot National Forest. Descending from White Salmon Glacier at about 10,200 feet to a terminus near 7,600 feet, it is notable for yellowish-brown rocks along its path and for a long history of retreat. The glacier has been shrinking for more than a century, losing 59 percent of its surface area between 1904 and 2006. It stands as one of Mount Adams’s many changing glaciers, showing the mountain’s active glacial landscape and its steady transformation over time.