Chester Springs. Earlier known as Yellow Springs. Resort since 1750. Washington's headquarters, Sept. 17, 1777, after Battle of Brandywine. Hospital for his soldiers during the winter encampment at Valley Forge, 1777-1778. Kimberton Rd. (PA 113) at Yellow Springs Rd., Chester Springs, PA by Pennsylvania Historical and Museum Commission Colour: blue Wikimedia: Flickr: Google Streetview OpenStreetMap