The view from the Portland Observatory, overlooking the city from Munjoy Hill on the East End. Photo courtesy of Greater Portland Landmarks

The Portland Observatory, America’s last remaining maritime signal tower, is both a National Historic Landmark and one of the more spectacular perches (it’s the highest point in the city) from which to survey all of Portland and its glistening harbor. Clear days are known to give visitors to the Munjoy Hill tower’s balcony a view of both the ocean’s horizon and the tip of Mount Washington in New Hampshire. And the views across the rooftops of homes and businesses, multiple other landmarks, and the streets of Portland are also remarkable.

The Portland Observatory’s initial purpose was to signal to shipowners when their vessels entered the harbor, using a system of flags. Photo courtesy of Greater Portland Landmarks

The octagonal, lighthouse-shaped building dates back to the early 1800s, when former sea captain Lemuel Moody used it to monitor the routes of ships up to 30 miles away with a telescope from the tower’s top. Ship owners paid Moody a fee to let them know – via a system of signal flags – when their ships were returning (otherwise, because of Portland’s deep harbor sheltered by a handful of islands, they wouldn’t be seen until they were almost in the harbor). The tower greatly increased the productivity and efficiency of Portland Harbor until the invention of two-way radio, at which point it was no longer needed. In the years following, it was donated to the city of Portland, which restored and reopened it in 1939.

Repairs were done again decades later when the nonprofit Greater Portland Landmarks took over the tower’s management in partnership with the city and began offering tours to the public. After another decade went by, it was renovated again to address various damages (including a beetle infestation) and reopened in 2000. And now this year, the observatory is undergoing a major redesign and expansion.

The tapered tower is 86 feet tall; its diameter is 32 feet at the base and 15 feet up at the top’s observation deck.

Guided tours offer a highly detailed look at the tower’s history – in addition to its use as a signal tower, it also served as a watchtower during several wartimes, from the War of 1812 to World War II – as well as the history of the area surrounding it. Tours are offered Memorial Day until Columbus Day. Note that there are 103 steps to the top; it’s a trek well worth the effort, but not for the faint of heart. The tower is currently handicapped-accessible on the first floor only.

Admission is $10 for adults; $8 for seniors, students and AAA members; $5 for children ages 6 to 16, and free for children under 6. Families are $30. To celebrate Flag Day every year, the observatory’s entrance fee is waived to all visitors. Flag Day is June 14.

Alexandra Hall is a longtime New England lifestyle writer who recently moved to Maine.