A superb example of Georgian style architecture, the Dey Mansion was General George Washington's Headquarters during the Revolutionary War in 1780. Today, the Mansion is filled with period antique furniture and conducts guided tours.

To provide guided interpretive tours of the historic site. To provide re-enactment programs of Revolutionary War military life and civilian lifeways during the eighteenth century. To provide lecture programs and other educational programming on the topics of George Washington, the Revolutionary War, eighteenth century decorative arts, and eighteenth century American Life.

Constructed between 1740-1750 by Dirck Dey, a Dutch-born planter, the mansion is an amalgam of Dutch and English influences, a rich and dramatic composition of country and urban elements that had few mid-18th century counterparts west of the Hudson River. Dey, in all probability, left the completion of the mansion to his son, Theunis. During the Revolution, Theunis commanded the Bergen County Militia. Colonel Dey offered the easterly side of the house to General Washington when the commander-in-chief use.