Sitka City and Borough is a city-borough located on the west side of Baranof Island in the Alexander Archipelago of the Pacific Ocean (part of the Alaska Panhandle), in the U.S. state of Alaska. It is the largest city in area in the United States. The borough seat is Sitka, the only incorporated section. Sitka, the "First City of Alaska," is the state's fourth-largest in terms of population.

The name Sitka (derived from Sheet’ká, a contraction of the Tlingit name Shee At'iká) means "People on the Outside of Shee," Sheet’-ká X'áat'l (often expressed simply as Shee) being the Tlingit name for Baranof Island. The town is often referred to as "Sitka-by-the-Sea."