Valley Forge National Historical Park is the site of the third winter encampment of the Continental Army during the American Revolutionary War from December 19, 1777 to June 19, 1778. The National Park Service preserves the site and interprets the history of the Valley Forge encampment. The park contains historical buildings, recreated enca…Valley Forge National Historical Park is the site of the third winter encampment of the Continental Army during the American Revolutionary War from December 19, 1777 to June 19, 1778. The National Park Service preserves the site and interprets the history of the Valley Forge encampment. The park contains historical buildings, recreated encampment structures, memorials, museums, and recreation facilities.