easternmost city of the United States, in Washington county, eastern Maine. It is situated on Moose Island, along Passamaquoddy Bay (bridged to the mainland) of the Atlantic Ocean, 126 miles (203 km) east of Bangor. Settled about 1780, it once included the town of Lubec (which is south and slightly farther east than Eastport) and was known as Moose Island, but upon incorporation as a town (1798) it was renamed for being the nation's most easterly port. It was captured by British troops during the War of 1812 (1812, War of) and remained under martial law until 1818, when it was returned to the United States under the terms of the Treaty of Ghent (Ghent, Treaty of). Eastport was the scene of considerable activity during the 1930s when the federal government began work on the Passamaquoddy Tidal Power Project to harness the exceptionally high tides (up to 27 feet 【8 metres】) of Passamaquoddy Bay for hydroelectric power. The project resulted in the construction of two tidal dams but was never completed.

Eastport's economy, once heavily dependent on sardine fishing and canning, has diversified. The city has become a major centre of the aquaculture industry; Atlantic salmon are farmed in offshore pens, and nori seaweed is cultivated. Eastport has a textile mill, and logs and paper products are shipped from the city's deepwater port. Tourism is important. Old Sow, said to be one of the largest whirlpools in the world, is nearby. Pleasant Point, site of the Passamaquoddy Indian Reservation, is just to the north, while across the water to the east is Roosevelt Campobello International Park on Campobello Island. Inc. city, 1893. Pop. (1990) 1,965; (2000) 1,640.