Britain obtained title in Jay's Treaty of 1794, while surrendering its sovereignty claims over Eastport on Moose, Frederick and Dudley islands in nearby Cobscook Bay.

[4][5] While neighbouring islands along the American coast to Boston relied on whaling, Grand Manan had fishing and shipbuilding.

In 1831 the Gannet Rock Lighthouse was built on a rocky islet south of Grand Manan, to protect shipping en route to Saint John, New Brunswick.

In 1857, the Lord Ashburton, was driven into the cliffs at the northern end of the island by hurricane-force winds to great loss of life.

[citation needed] By the late Victorian era, Grand Manan had been discovered by a new breed of explorers—the "tourists"—who began visiting the island in steady numbers, weaving themselves into the fabric of its close-knit, isolated society.

Pulitzer Prize–winning author Willa Cather loved the island's unspoiled solitude, while painters such as Alfred Thompson Bricher and John James Audubon came to Grand Manan and its outlying islands to capture what they believed to be its "unique majesty", documenting its varied geography and indigenous fauna.

Due to limited access, 90-metre (300 ft) cliffs and high winds, the western side of the island is not residentially developed.

The Fundy basalts are themselves a small portion of the Central Atlantic Magmatic Province which was formed in a volcanic event preceding the breakup of the supercontinent Pangaea in the Early Jurassic.

They include zeolite minerals such as chabazite, mesolite, stilbite, and heulandite, plus attractive quartz-related amethyst, agate, jasper, and many others.

A few meters of siltstone are exposed under the basalt along the western shoreline, which by analogy with the Blomidon Formation in Nova Scotia must include the Triassic-Jurassic boundary.

[9] Harbours along the eastern shoreline were created by the erosion of complex fault and fold structures in ancient metamorphosed sedimentary and volcanic rock formations.

Although originally they were igneous and sedimentary rocks such as basalt, sandstone, and shale, the eastern formations have been metamorphosed into greenstone, phyllite, argillite, schist, quartzite, and other foliated types.

Together with ocean salmon farms, dulse, rock weed and clam digging, many residents make their living "on the water."

Visitors and retirees often purchase real estate and remain on the island through the summer months or reside permanently.

[citation needed] New York architect Michael Zimmer established the Sardine Museum and Herring Hall of Fame.

Other interesting finds on Grand Manan are magnetic sand, and "The Hole-In-The Wall" located in Whale Cove in the village of North Head.

The Anchorage Provincial Park can be found on the island's southeastern coast between the communities of Grand Harbour and Seal Cove.

A full 63% of the population 15 years and older had at least a high school certificate or equivalent, with 22% having at least some college, CEGEP, or university training.