Southeast Alaska, often abbreviated to southeast or southeastern, and sometimes called the Alaska(n) panhandle, is the southeastern portion of the U.S. state of Alaska, bordered to the east and north by the northern half of the Canadian province of British Columbia. The majority of southeast Alaska is situated in Tlingit Aaní, much of which is part of the Tongass National Forest, the United States' largest national forest. In many places, the international border runs along the crest of the Boundary Ranges of the Coast Mountains. The region is noted for its scenery and mild, rainy climate.

Alaska is a non-contiguous U.S. state on the northwest extremity of North America. It borders the Canadian province of British Columbia and the Yukon territory to the east; it shares a western maritime border in the Bering Strait with Russia's Chukotka Autonomous Okrug. The Chukchi and Beaufort Seas of the Arctic Ocean lie to the north and the Pacific Ocean lies to the south. Technically a semi-exclave of the U.S., it is the largest exclave in the world.