Portland Observatory surveys history and the sea

From the top of the 86-foot-tall Portland Observatory, the view (below) sweeps across Casco Bay.
photos by David Lyon for The Boston Globe
From the top of the 86-foot-tall Portland Observatory, the view sweeps across Casco Bay.

One in a series on National Historic Landmarks in New England.

PORTLAND, Maine — Historic sites remind us of how far we have come, and the Portland Observatory is certainly a case in point. In 1807, when former sea captain Lemuel Moody built the tower on Munjoy Hill, “sight was the main means of communication,” guide Judy Carll told a small group of cellphone-toting tourists, “and just about every seacoast city had a signal tower.”

Sitting among the cow pastures on the high east end of the Portland peninsula, the 86-foot-tall tower stood 160 feet above Casco Bay and had a clear view from the harbor out to the Atlantic Ocean. Standing on the observation deck, Moody could use a powerful telescope to spot ships up to 30 miles out to sea — still a full day’s sail from the harbor. For merchants who subscribed to his services, he would raise a flag to let them know that their ship was coming in. “That way, they could get the docks ready for unloading,” said Carll. “Time is money and Moody saved them lots of money.”

Moody also took weather observations and sold them to a local newspaper. “He was Portland’s first weatherman,” said Carll. He was also something of an entrepreneur. He surrounded his “ugly brown tower,” as Portlanders called it, with an entertainment complex that included a bowling alley and a dance hall, thus creating an early tourist attraction.

David Lyon for The Boston Globe
The views from the observation deck of the Portland Observatory.

Only the tower remains today, shoehorned among the shops and homes that eventually took over Munjoy Hill. “When the tower first went up, people said it would blow down in the first winter,” said Carll. Instead, it is thought to be the only remaining maritime signal tower in the country — and a testament to its sturdy design. The tower is anchored by 122 tons of rock at the base and its octagonal frame was formed with timbers from tall pine trees floated down the Presumpscot River. The tower gets narrower as it grows taller, allowing strong winds to flow around it rather than knock it down.

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A curving interior staircase leads to the observation deck. With only 86 steps from the reception area to the top, it’s a pretty easy climb and Carll doesn’t rush. She stops several times so that visitors can look at the displays on the landings, including one that recounts the Great Fire of 1866 that destroyed much of the city before it burned out near Munjoy Hill, thus sparing the tower. But the building did face other threats. Another display details the ambitious 1998-2000 restoration that rescued it from the depredations of moisture and a powder post beetle infestation. Restorers “literally took the building apart,” Carll says, noting that about 85 percent of it remains original.

In 1923, newfangled two-way radios spelled the end of the tower’s days of “signalizing,” as Moody had dubbed it. But the view from the observation deck is as glorious as ever. Signs in the cupola help identify Portland Head, Spring Point Ledge, and Portland Breakwater (a.k.a. Bug) lighthouses, as well as the 19th-century forts Scammel and Gorges. On a clear day, look north-northwest to see Mount Washington in the distance. Or do as Moody did, and look southwest to spy the ships bound for Portland Harbor.

PORTLAND OBSERVATORY 138 Congress St., 207-253-1800, Open through Oct. 14, daily 10 a.m.-5 p.m. (Last tour 4:30.) Sunset tours July 18-
Sept. 5, 5-8 p.m. Adults $9, seniors and students $8, ages 6-16 $5.

Patricia Harris and David Lyon can be reached at