King Slough is a water passage between Farm Island and Dry Island in the Stikine River delta, about 22 miles (36 km) southeast of Petersburg and 11 miles (18 km) north-northwest of Wrangell, Alaska. The slough is about 5 miles (8 km) long from North Arm Stikine River to Dry Strait and was named in 1951 by the U.S. Geological Survey, presumably for the Chinook salmon that are locally called king salmon. The Stikine River estuary is approximately 8 miles (13 km) wide and 16 miles (26 km) long and all of it is in the Stikine-LeConte Wilderness, a major resting and feeding area for waterfowl along the Pacific Flyway. The wilderness is part of Tongass National Forest, which is managed by the U.S. Forest Service.

The Stikine River is about 380 miles (610 km) long and is navigable for approximately 130 miles (210 km) upstream from its delta. It was used historically by the coastal Tlingit as a transportation route to the interior region. The Stikine River valley is relatively narrow and the surrounding mountains are steep, rugged, and contain numerous glaciers. Meltwater from these glaciers has a high silt content, giving the Stikine River a milky appearance. The river delta consists of extensive mudflats, numerous sloughs of varying widths, and large islands. The delta flats of the Stikine River are a major resting and nesting area for migratory birds. A variety of fish, including king salmon, are found in the delta, and up to 2000 bald eagles may congregate in the mouth of the river following a run of smelt. The river delta is highly braided with three main navigable channels that are shallow. Historically, riverboat operators relied upon the incoming tides to pass through this area, proceeding cautiously as deckhands called out the depths.

The Submerged Lands Act of 1953 gave states title to all land beneath navigable waters. The Alaska Statehood Act incorporated the provisions of the Submerged Lands Act, giving the state title to the submerged lands in Alaska. This means that all submerged lands beneath navigable waters even if surrounded by Tongass National Forest, belong to the State of Alaska. In 2005, the State of Alaska filed an application for a recordable disclaimer of interest for the bed of the Stikine River from its mouth to the United States-Canada International Boundary, a distance of approximately 27 miles (44 km). The State of Alaska also applied for lands underlying all of the named interconnecting sloughs including King Slough. Read more here and here. Explore more of King Slough and the Stikine River estuary here: