The Knox Covered Bridge is located within Valley Forge National Historical Park, crossing Valley Creek in a setting surrounded by the history and natural beauty of the Valley Forge landscape.
The original bridge was built in 1851 at a cost of $843. It spanned approximately 50 feet and was constructed of white pine, a lightweight and durable wood valued for its resistance to insects and weather.
Like other covered bridges of its era, the structure was enclosed to protect the wooden timbers from rain, snow, and sunlight. The covered superstructure helped keep moisture out of the joints, reducing the risk of freezing and splitting during the winter and rot during the warmer months. By protecting the wood from the elements, the covering significantly extended the life of the bridge.
In 1865, the original bridge was washed away by a flood and replaced that same year at a cost of $1,179. The replacement bridge had a longer, 65-foot span. In 1958, the bridge was damaged by fire. When it was subsequently rebuilt by the Commonwealth, steel girders were added to reinforce the historic structure.
For many years, the bridge was known as the Valley Forge Dam Bridge. During the nineteenth century, numerous mills and factories operated along Valley Creek, using water power from a dam located near what is now Route 23. The dam created a lake that was described as a “very pretty body of water.” However, with the water level only about a foot below the roadway, the dam also contributed to periodic flooding.
Today, the bridge is generally known as the Knox Bridge, although the origin of the name is associated with two prominent figures in American history: Senator Philander C. Knox and General Henry Knox.
In 1903, Senator Philander C. Knox purchased 256 acres of land near the bridge and moved into the historic farmhouse west of the bridge. During the Valley Forge encampment, that farmhouse had served as the quarters of General William Maxwell. Across the bridge, the farmhouse to the east had served as the quarters of General Henry Knox, adding another layer of Revolutionary War history to the bridge and its surroundings.
Today, the Knox Covered Bridge stands as a reminder of both Pennsylvania’s covered-bridge heritage and the rich history preserved throughout Valley Forge National Historical Park.
