Bath is a city in Sagadahoc County, Maine, in the United States. The population was 8,514 at the 2010 census, and 8,329 as of 2018; the population has had a change of -10.2% since 2000. It is the county seat of Sagadahoc County, which includes one city and 10 towns. The city is popular with tourists, many drawn by its 19th-century architecture. It is home to the Bath Iron Works and Heritage Days Festival, held annually on the Fourth of July weekend. It is commonly known as "The City of Ships". Bath is part of the metropolitan statistical area of Greater Portland.
Abenaki Indians called the area Sagadahoc, meaning "mouth of big river". It was a reference to the Kennebec River, which Samuel de Champlain explored in 1605. Popham Colony was established in 1607 downstream, together with Fort St George.