Southeast Alaska is the northern terminus of the Inside Passage, a protected waterway of convoluted passages between islands and fjords, beginning in Puget Sound in Washington state. This was an important travel corridor for Tlingit and Haida Native peoples, as well as gold-rush era steamships. In modern times it is an important route for Alaska Marine Highway ferries as well as cruise ships. Southeast Alaska has a land area of 35,138 square miles (91,010 km2) comprising seven entire boroughs and two census areas, in addition to the portion of the Yakutat Borough lying east of 141° West longitude. Although it has only 6.14 percent of Alaska's land area, it is larger than the state of Maine, and almost as large as the state of Indiana. The Southeast Alaskan coast is roughly as long as the west coast of Canada. The 2010 census population of Southeast was 71,616 inhabitants, about 45 percent of whom were concentrated in the city of Juneau.
It includes the Tongass National Forest (which manages Admiralty Island National Monument and Misty Fjords National Monument), Glacier Bay National Park, Sitka National Historical Park, Alaska's Inside Passage, and myriad large and small islands. The largest islands are, from North to South, Chichagof Island, Admiralty Island, Baranof Island, Kupreanof Island, Revillagigedo Island and Prince of Wales Island. Major bodies of water of Southeast Alaska include Glacier Bay, Lynn Canal, Icy Strait, Chatham Strait, Stephens Passage, Frederick Sound, Sumner Strait, and Clarence Strait.
Southeast Alaska is a temperate rain forest within the Pacific temperate rain forest zone, as classified by the World Wildlife Fund's ecoregion system, which extends from northern California to Prince William Sound. The most common tree species are sitka spruce and western hemlock. Wildlife includes brown bears, black bears, the endemic Alexander Archipelago wolf, Sitka black-tailed deer, humpback whales, orcas, five species of salmon, bald eagles, harlequin ducks, scoters, and marbled murrelets.
The Ecological Atlas of Southeast Alaska, published by Audubon Alaska in 2016, offers an overview of the region's landscape, birds, wildlife, human uses, climate change, and more, synthesizing data from agencies and a variety of other sources.
Major cities are Juneau, Ketchikan, and Sitka. Other towns are Petersburg, Wrangell, Metlakatla, Haines, Hoonah, Angoon, Kake, Craig, Klawock, Thorne Bay, Yakutat, Skagway, and Gustavus. There are also many towns and villages with around 100 people, such as Baranof Warm Springs, Edna Bay, Elfin Cove, Excursion Inlet, Funter Bay, Meyers Chuck, Pelican, Port Alexander, Port Frederick, Port Protection, and Tenakee Springs. This region is also home to the easternmost town in Alaska, Hyder.
This area is the traditional homeland of the Tlingit, and home of a historic settling of Haida as well as a modern settlement of Tsimshian. The region is closely connected to Seattle and the American Pacific Northwest economically and culturally.