Conservation Sale Protects Arden House

Image Credit: Greg Miller

NEW YORK, NY — November 2, 2011—  Surrounded on three sides by more than 110,000 acres of permanently protected state parkland, the Arden House mansion in Harriman, New York is a historic and architectural gem of the Hudson River Valley.

Because of its historical significance and proximity to so much protected land, the Open Space Institute acquired the estate in 2007. Today it was announced that OSI’s land acquisition affiliate, the Open Space Conservancy, has sold Arden House and the surrounding 452 acres for $6.5 million to the Research Center on Natural Conservation, Inc., a nonprofit organization dedicated to discovering innovative natural conservation methods, organizing forums to discuss contemporary environmental preservation issues and studying the effects of global warning. 

The Center was identified as an ideal buyer because of its capacity to conserve both the land and historic buildings. It will take immediate possession of Arden House and plans to upgrade the facilities.

Built by railroad magnate E.H. Harriman in 1909, the 100,000-square-foot mansion is a sprawling, three-story granite and stone structure that sits just 40 miles north of Manhattan. The secluded surrounding property incorporates the 125-acre Cranberry Lake and is protected with a conservation easement as part of the sale to the Research Center.

The Harriman family occupied Arden House until 1933. The house was established as America’s first conference center in 1950, when the family donated the property to Columbia University. It was added to the National Register of Historic Places in 1966.

In addition to Arden House, the Harriman family created a lasting conservation legacy in the early 20th century by acquiring nearly 70,000 additional Hudson Valley acres—lands that OSI and other organizations later helped permanently protect as Bear Mountain, Harriman and Sterling Forest state parks.

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