National Historic Landmark

Portland Observatory

Portland, Cumberland County, Maine
Listed
April 23, 1973
Type
Building
Period
Industrial
Ref No.
73000122

About this property

The Portland Observatory is a historic maritime signal tower at 138 Congress Street in the Munjoy Hill section of Portland, Maine. Built in 1807, it is the only known surviving tower of its type in the United States. Using both a telescope and signal flags, two-way communication between ship and shore was possible several hours before an incoming vessel reached the docks. The tower was designated a National Historic Landmark and a National Historic Civil Engineering Landmark in 2006; it is now managed by Greater Portland Landmarks, a local historic preservation nonprofit. It is open to the public as a museum.

Location

138 Congress St.
Portland, Cumberland County, Maine
43.66535, -70.24824

Categories

COMMUNITY PLANNING AND DEVELOPMENTARCHITECTURECOMMUNICATIONS
National Register nomination ›
Sources

Property data from the National Register of Historic Places, National Park Service (public domain).

Description adapted from Wikipedia under the Creative Commons Attribution-ShareAlike 4.0 International License.

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Everything a full report reveals about Portland Observatory

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Overview
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The Land
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Geology
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LiDAR Terrain
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Conflict & War
The battles, raids and skirmishes fought near here, across every era of American conflict.
The Civil War
The Civil War on this ground, 1861 to 1865: who held it, and the battles, camps and regiments nearby.
The Soldiers
The men who marched from here in the Civil War, named and traced where the record allows.
Native Heritage
The Native nations who held this land, mapped across time from before European contact to today.
Settlement
Who claimed and held this ground, from Indigenous homelands through the colonial powers to the United States.
The Community
How the town grew, who came, and what kind of place it became, traced through the census record.
Rivers & Rail
The rivers, canals and railroads that connected this place between 1830 and 1911.
Notable People
The people born, buried or genuinely tied to this exact place, with their stories.
Historical Maps
Historic maps of the location layered over how it looks today.
Finds & Access
Museum objects tied to the area, and the laws on searching, collecting and access here.
Literature
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Spotlight
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Points of Interest
The most significant historic sites and landmarks near the location, and why they matter.
Timeline
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Nearby Historic Sites

Green Memorial A.M.E. Zion Church
Industrial
0.1 mi
St. Lawrence Church
Industrial
0.2 mi
Eastern Cemetery
Colonial
0.2 mi
Abyssinian Meeting House
Industrial
0.2 mi
North School
Civil War
0.3 mi

Nearby Battles

Battle of Casco Bay (Falmouth 1690)
1690Colonial
0.4 mi
Battle of Casco Bay (Fort Loyal) 1690
1690Colonial
0.4 mi
Siege of Fort Loyal Casco 1690
1690Colonial
0.5 mi
Siege of Fort Loyal (Falmouth) 1690
1690Colonial
0.5 mi

Questions about this property

When was Portland Observatory listed on the National Register?

Portland Observatory was listed on the National Register of Historic Places on April 23, 1973.

What type of historic resource is Portland Observatory?

Portland Observatory is classified as a building in the National Register of Historic Places.

Is Portland Observatory a National Historic Landmark?

Yes. Portland Observatory has been designated a National Historic Landmark (NHL), the highest level of federal recognition for historic properties in the United States.

What is the period of significance for Portland Observatory?

The period of significance for Portland Observatory is recorded as the industrial era.

Can I research the history near Portland Observatory?

Yes. Aubrey Research reports search National Register listings, battlefield records, land patents, and other primary historical sources within any radius of a US address. A report for an address near Portland Observatory will include this listing and all other historical records in the area.

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