Knox Covered Bridge - Valley Forge National Park - Wayne, PA - American Guide Series on Waymarking.com

At 1.6 m. is a junction with Yellow Spring Road.
Left (straight ahead) on Yellow Spring Road, across a white covered bridge spanning Valley Creek, to a fork, 0.2 m. --- Pennsylvania: A Guide to the Keystone State, 1940; page 409

Originally built in 1851 at a cost of $843, its span was 50 feet. The bridge was made of white pine, light in weight and resistant to worms and weather. Like other covered bridges, it was covered for protection from the weather, to keep off the rain, snow and sun. The superstructure over the bridge kept water out of the joints, where it might freeze during the winter or cause rotting in the summer, and also kept the bridge from drying. The 1851 bridge was washed away in 1865 by a flood. A replacement was built that year at a cost of $1,179. With slightly longer a 65-foot span. In 1958 the bridge was damaged by fire. When it was rebuilt by the State, steel girders were added to reinforce and strengthen it. The bridge is only one lane wide. Once across, you can access Lafayette's Quarters, Lord Sterling's Headquarters, and Maxwell's Quarters which has been turned into the Wilcox Memorial library. It is located in Tredyffrin Township, Montgomery County, Pennsylvania. The bridge was closed down for a few weeks last year for restoration and painting.

For many years the bridge was known as the Valley Forge Dam Bridge. In the 19th century there were a number of mills and factories along The Valley Creek with a dam near what is now Route 23 providing water power for their operation. The lake formed by the dam was a "very pretty body of water" but with the water level only a foot or so below the road, it also caused flooding from time to time.