Tetlin National Wildlife Refuge is a dynamic landscape made up of forests, wetlands, tundra, lakes, mountains and glacial rivers bounded by the snowy peaks of the Alaska Range. This upper Tanana River valley has been called the "Tetlin Passage," because it serves as a major migratory route for birds traveling to and from Canada, the lower 48 and both Central and South America. Many of these birds breed and nest on the refuge. Others pass through on their way to breeding and nesting grounds elsewhere in the state. Migrants, including ducks, geese, swans, cranes, raptors and songbirds, begin arriving in the valley in April, and continue into early June. An estimated 116 species breed on Tetlin during the short summer, when long days and warm temperatures accelerate the growth of plants, insects and other invertebrates, providing a ready source of rich foods for nesting birds. Tetlin Refuge also supports a variety of large mammals. Dall sheep dot the higher slopes while moose feed upon the tender new growth that springs up in the wake of frequent lightning caused fires. Wolves, grizzly and black bears and members of three different caribou herds range over the refuge. Two of the six known humpback whitefish spawning areas in the Yukon River drainage are located within the refuge. Along with caribou and moose, these fish are important subsistence resources for area residents. Arctic grayling, northern pike and burbot are also found in the refuge's many streams and lakes.

The Tetlin Refuge headquarters is located in Tok at the corner of Midnight Sun and Borealis Avenue. The community of Tok is located 94 miles northwest of the U.S./Canada border, and is 205 miles southeast of Fairbanks, Alaska. The refuge's visitor welcome station is located at milepost 1229 on the Alaska Highway, just seven miles from the U.S./Canada border. The northern boundary of Tetlin Refuge extends 65 miles along the Alaska Highway. Foot access to the northern portion of the refuge is available along the Alaska Highway from the U.S./Canada border at milepost 1221.5 to milepost 1242 of the Alaska Highway. Small boat/canoe access is available at Desper Creek at milepost 1225.4, the Chisana River bridge in Northway at milepost 1264, the old Riverside airstrip at milepost 1281 and at the Tanana River bridge at milepost 1303.6. Access to the interior of the refuge is limited to watercraft, small ski/float equipped airplane, foot travel or snowmachine.