Portsmouth Naval Shipyard

shipyard, Kittery, Maine, United States

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July 1, 2026

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The Portsmouth Naval Shipyard is a U.S. naval facility located in Kittery, Maine, across the Piscataqua River from Portsmouth, New Hampshire. Established in 1800, it was the country's first naval shipyard and is renowned for building and maintaining submarines. The shipyard has been a significant shipbuilding center since Revolutionary War times, with the first ship to fly the American flag, John Paul Jones's Ranger, launched there in 1777. It was also the site of the 1905 Treaty of Portsmouth, which ended the Russo-Japanese War. The facility is manned by civilian workers and administered by engineer duty officers, responsible for building, repairing, and outfitting warships.1234

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Kittery
The Portsmouth Naval Shipyard (1800), which from the mid-1950s to 1971 built nuclear submarines and now overhauls and repairs them, is in Kittery. The Treaty of Portsmouth (1905), ending the Russo-Japanese War, was signed there. Nearby in South Berwick is the birthplace of novelist Sarah Orne…
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The Portsmouth Naval Shipyard (1800), which from the mid-1950s to 1971 built nuclear submarines and now overhauls and repairs them, is in Kittery. The Treaty of Portsmouth (1905), ending the Russo-Japanese War, was signed there. Nearby in South Berwick is the birthplace of novelist Sarah Orne…
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New Hampshire
Economy
The Portsmouth Naval Shipyard (actually located across the harbor from Portsmouth at Kittery, Maine) is one of the largest employers in the seacoast region. Established in 1800 as the country’s first naval shipyard, it is now renowned for building and maintaining submarines.
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The Portsmouth Naval Shipyard (actually located across the harbor from Portsmouth at Kittery, Maine) is one of the largest employers in the seacoast region. Established in 1800 as the country’s first naval shipyard, it is now renowned for building and maintaining submarines.
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