Photo Credit: Jerry Monkman


Places We Work New York Hudson River Valley Project List


Benedict Arnold rode through it trying to escape to the British. New York Governor Hamilton Fish, later to become Secretary of State under President Ulysses Grant, lived on it. Grant and President Abraham Lincoln both visited it. Today, Glenclyffe, a 93-acre parcel of land on the Hudson River in the Highlands, is preserved through the efforts of OSI and its partners.

With the assistance of local volunteers, OSI recently converted Arnold’s escape route into a public trail. The 1.8 mile Glenclyffe Loop comprises one of the newest segments of the Hudson River Valley Greenway Trail.   The Loop includes a section of “Marcia’s Mile,” a path blazed in memory of the late Marcia Favrot, a dedicated conservationist and an active member of the Philipstown community.

In the early part of the 20th century, a Capuchin Franciscan monastery was located on the property. When OSI acquired the land in 2001, it found partners to use the large buildings. The 72,000 square foot Georgian brick and marble friary was sold to the Garrison Institute, a multi-faith nonprofit organization, and another building—a 34,000 square foot former dormitory—is used by the Philipstown Department of Recreation.

Glenclyffe is located immediately south of Arden Point State Park on Rt. 9D in Garrison, Philipstown Town, in Putnam County.



Capital District
Hudson River Valley

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