The 1700 house was owned by Patriot Johannes DeWint during the Revolution and is the oldest building in Rockland County. There George Washington signed the death warrant of British Major John Andre, who plotted with Benedict Arnold to surrender West Point to the enemy. In 1783 Washington entertained British General Sir Guy Carleton to negotiate the vanquished army's evacuation of NYC. The house's rooms reflect Washington's occupancy. A 19th-century carriage house contains artifacts related to Washington, Andre, and Arnold.