Yahtse Glacier flows to a tidewater terminus in Icy Bay between Guyot Hills to the west and Karr Hills to the east, about 152 miles (245 km) east-southeast of Cordova and 71 miles (115 km) northwest of Yakutat, Alaska. The glacier originates at 8,200 feet (2,500 m) on the south flank of Mount Miller in Barkley Ridge and flows southeast for 40 miles (65 km) through Wrangell-Saint Elias National Park and Preserve. The glacier name was proposed in 1963 by Austin Post of the US Geological Survey, following the retreat of Guyot Glacier, which formed a separate ice stream on the west side of Guyot Hills. It derives from the Yahtse River, which may once have flowed into Icy Bay in this area. Bedrock exposures in the ice stream represent the Yakutaga Formation of the Yakutat terrane—an active-margin basin filled with 16,000 feet (5,000 m) of glacial sediment, thrust and uplifted by compression between the Pacific and North American plates. The Yakataga Formation is the world’s best-exposed and most complete late Cenozoic (about 34 million years ago to the present) record of cool-temperate, glacially influenced marine sedimentation, represented by deep-basin turbidites, glacial debris flows, diamictites, and shallow marine sandstones.

Harold W. Topham, a mountaineer with the Alpine Club of England, attempted the summit of Mount St Elias (18,008 feet/5,486 m) via the Tyndall Glacier in 1886 and later presented his findings to the Royal Geographical Society. His party traveled from London to Montreal by ship, then overland to British Columbia, onward by ship to Victoria on Vancouver Island, and on to Sitka, then the capital of the District of Alaska. From Sitka, a schooner took them to Alsek, and canoes to Yakutat, where they hired Tlingit guides and paddled to Icy Bay. They landed on the delta of what Topham called the Yahtse-Tah River—meaning “muddy river”—which once served as a primary outlet for the western Malaspina Glacier. Tlingit oral tradition tells of a large bay running inland to the base of Mount St Elias, with a village at its head on swampy ground called Yahtse. The mountain was known as Yahtse-tah-shah (tah: harbor; shah: peak). One day, ice was seen advancing rapidly down the bay; the people escaped as it struck the shore, turned, and swept to the sea, obliterating the village. After the Icy Bay glaciers retreated in the 20th century, the Malaspina’s outlet shifted to the Caetani River, and the Yahtse River channel was largely abandoned by the early 21st century.

When George Vancouver visited the area in 1794, a glacier front extended to the outer coast; the “Icy Bay” he recorded was in fact a small embayment between two lobes of the Malaspina Glacier, near the site of the modern Yahtse River delta. The present Icy Bay and its tributary fjords were exposed by more than 25 miles (40 km) of tidewater glacier retreat during the 20th century. Remnants of ancient shoreline forests found in deglaciated areas have yielded radiocarbon dates indicating two major glacier expansions in the past 2,000 years. Dominant tree species around outer Icy Bay are western hemlock, mountain hemlock, and Sitka spruce; inner Icy Bay also supports black cottonwood and Sitka alder, the latter forming dense thickets along tributary fjord shores. This distribution reflects ecological succession: fast colonizers such as alder pioneer recently deglaciated ground, while the broader pattern represents a seral sequence advancing from bare substrate toward climax community. Read more here and here. Explore more of Yahtse Glacier and Icy Bay here: