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By the Numbers: Affiliated Areas


Located about 40 miles northwest of Madison, the nearly 10,000-acre Devil's Lake State Park, Wisconsin's most heavily-visited state park, is a unit of the Ice Age National Scientific Reserve. Wisconsin DNR photo.

Affiliated Areas are not national parks. In fact, they are neither owned nor administered by the federal government. They do preserve important elements of our country’s heritage, however, and they do get some technical assistance and limited financial aid from the National Park Service.

There are currently 23 officially designated Affiliated Areas. Here are some of their vital statistics. For additional information, see pp. 96-101 of the National Parks Index: 2009-2011.


Acreage of the largest Affiliated Area, the Pineland National Reserve. Better known as the Pine Barrens, this huge area of southern New Jersey is more than twice the size of Great Smoky Mountains National Park. Designated as an Affiliated Area in 1978, then designated a Biosphere Reserve in 1983, this “unique ecosystem of historic villages and berry farms amid vast pine-oak forests, extensive wetlands, and diverse species of plants and animals” is co-managed by local, state, and federal governments and the private sector.


Distance, in miles, between Washington, DC and the most remote Affiliated Area, American Memorial Park. Located on Saipan in the Northern Mariana Islands (which has an autonomous Commonwealth relationship with the United States), the WW II-themed American Memorial Park is, quite literally, about as far away from Washington, DC as it could possibly be. That’s because Earth’s circumference is ~24,880 miles (average of the equatorial and meridional circumferences), and half of that -- i.e., “half way around the world” – is 12,440 miles.


Percentage of Affiliated Areas located in the eastern United States. Only six of the 23 Affiliated Areas are located west of the Mississippi River – and that includes the one in Saipan.


Years since the oldest existing Affiliated Area was designated. Jamestown National Historic Site, which is located on Jamestown Island adjacent to Colonial National Historical Park, was designated on December 18, 1940 and is now owned and administered by the Association for the Preservation of Virginia Antiquities.


Median size, in acres of an Affiliated Area. Even this number fails to convey how small Affiliated Areas tend to be. At least six are less than one acre in size, and one-third or more are smaller than four acres.


Number of Affiliated Areas that are designated as National Historic Sites. The fact that nearly half of all Affiliated Areas bear this designation serves as a strong reminder that National Historic Site shouldn’t be considered synonymous with National Park System unit.


Number of separate units in Wisconsin’s continental glaciation-themed Ice Age National Scientific Reserve. Like the clumsily-titled New Jersey Coastal Heritage Trail Route, a discontinuous vehicular trail linking numerous sites along a 300 mile stretch of the Atlantic Coast, the Ice Age National Scientific Reserve illustrates that Affiliated Areas can be quite fragmented. Each of the nine units in the 32,500-acre Affiliated Area is administered by the Wisconsin Department of Natural Resources as a park recreational area, natural area, or wildlife area.


Number of Affiliated Areas that are jointly administered by the United States and Canada. One is the 2,330-acre International Peace Garden, an Affiliated Area that straddles the U.S.-Canada border in the state of North Dakota and the province of Manitoba. The state of North Dakota owns the 888-acre U.S. portion, which is administered by International Peace Garden, Inc. The U.S. and Canada also share administrative responsibilities for the Roosevelt-Campobello International Park, an Affiliated Area that preserves the summer retreat home of President Franklin Delano Roosevelt. Although this property is located in the Canadian province of New Brunswick, a little slice of it is only accessible from the United States.

Number of former Affiliated Areas that Congress has added to the National Park System through redesignation in recent years. In 2003, the McLoughlin House National Historic Site, a former Affiliated Area, was incorporated into the National Park System as a sub-unit of Fort Vancouver National Historic Site. The sub-unit actually consists of two adjacent houses -- the McLoughlin House (home of chief factor John McLoughlin) and the Barclay House (home of explorer Forbes Barclay, McLoughlin’s associate). In 2009, Port Chicago Naval Magazine National Memorial, an Affiliated Area designated in 1992, became the 392nd unit of the National Park System. The new NPS unit, which is located on an active military base near San Francisco, was the site of a July 17, 1944, munitions explosion that killed 320 and injured 400.


Number of former National Park System units that Congress has redesignated as Affiliated Areas in recent years. Oklahoma City National Memorial, a National Symbolic Memorial that Congress authorized in 1997 to commemorate the April 19, 1995, domestic terrorist bombing of the Alfred P. Murrah Federal Building (168 people killed and over 650 injured), was redesignated as an Affiliated Area on January 23, 2004. The memorial is now owned and operated by the private foundation that originally raised the money for the memorial and museum. The National Park Service, however, continues to provide the same level of interpretive services it provided when the site was part of the National Park System.


Listed acreage of the smallest Affiliated Area, the Benjamin Franklin National Memorial. This Affiliated Area consists of a single huge statue of Franklin (sculpted by James Earle Fraser) in the rotunda of the Franklin Institute at 222 North 20th Street in Philadelphia.

** Traveler[/i] thanks to Sabattis, who contributed importantly to this article.


Thanks for this article; the affiliated areas deserve some attention once in a while.

I'm curious about there being only 2 former affiliated areas. I have memories of seeing somewhere that the Arnold Aboretum in Boston was formerly an affiliated area.... but have never been able to find a corroborating source. I guess you weasel-worded it to only be those added to the National Park System "in recent years." ;-)

Weasel-worded? Moi? The very idea!

What year did the NPS begin its affiliated areas program?

I don't know when the term Affiliated Areas was first used, or by what authority. Perhaps a more knowledgable reader can help?
This is what the NPS has to say by way of defining Affiliated Areas:
Affliated Areas: In an Act of August 18, 1970,
the National Park System was defined in law as, "any area of land
and water now or hereafter administered by the Secretary of the Interior
through the National Park Service for park, monument, historic, parkway,
recreational or other purposes." The Affiliated Areas comprise a
variety of locations in the United States and Canada that preserve significant
properties outside the National Park System. Some of these have been recognized
by Acts of Congress, others have been designated national historic sites
by the Secretary of the Interior under authority of the Historic Sites
Act of 1935. All draw on technical or financial aid from the National
Park Service.  

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