OSI Hudson River Valley Projects

Photo Credit: Jerry Monkman

Hudson River Valley

Projects » New York » Hudson River Valley

Arden House

Arden House

Located in the Town of Woodbury, New York, Arden House was completed in 1909 by E.H. Harriman. The house was built at the highest point on Mount Orama.


Arden Point State Park

Visitors entering Arden Point State Park from the Garrison train station in Philipstown can cross the tracks to a wooded trail that meanders along the edge of the Hudson River.

Clear Lake

Clarence Fahnestock State Park

Since 1990, the Clarence Fahnestock Memorial State Park has doubled in size. Once approximately 6,000 acres, more than 14,000 acres are protected.


Constitution Marsh Hudson River

Constitution Marsh

In 1998, the Open Space Institute protected a key four-acre inholding adjacent to the 270-acre Constitution Marsh Sanctuary, managed by the National Audubon Society.

Dockside Hudson River 2


When early Dutch explorers sailed into this section of the Hudson, they called it “Wey Gat” or Wind Gate, later translated as Northgate and today known as Dockside Harbor.



In 2001 OSI acquired the Glenclyffe property which sits along the Hudson River.  In the early part of the 20th century, a Capuchin Franciscan monastery was located here.


Manitou Point Preserve

Wooded forests, the Hudson River, public hiking trails, and a house that recalls the days of the grand Hudson River Estates all await visitors to Mystery Point (Manitou Point Preserve).


North Redoubt Preserve

Featuring the remains of a Revolutionary War fortress, the 20-acre North Redoubt Preserve sits atop a bluff overlooking the Hudson River.


Philipstown Town Park

In 1994, OSI acquired the former property of the Malcolm Gordon School, a 52-acre plot on one of the most scenic sites in the Hudson Highlands to help create a town park.


Schunnemunk Mountain

An hour north of New York City, Schunnemunk Mountain, with an elevation of 1,700 feet, has long been a mecca for hikers from both southeastern NY and northern NJ.


Sterling Forest

Sterling Forest State Park is the second-largest park in the State of New York. Considered a critical link between Harriman State Park to the east and northern New Jersey to the west.

Washington's Headquarters

Washington's Headquarters

In preparation for the final days of the Revolutionary War in 1782 and 1783, General George Wahington set up headquarters at the Hasbrouck family farmhouse.

Washington's Lookout

Washington's Lookout

A rocky promontory on the flanks of Buckberg Mountain this site was reputedly used by General George Washington and Colonel “Mad” Anthony to plan a surprise attack.

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