Construction of the iron viaduct began during 1881, starting with the placement of the stone piers. When completed during 1882, the Kinzua Bridge Viaduct was the highest railroad viaduct in the world. It was constructed as an alternative to laying an additional eight miles of track over rough terrain along the line leading to McKean County’s coal, timber, and oil lands.
Built of iron, the original viaduct was approximately 301 feet high, 2,053 feet long, and weighed 3,105,000 pounds. The towers were a patented design called Phoenix Columns. The columns were lighter in weight and had greater strength than cast iron columns of similar shape and size.
By 1900, it became necessary to rebuild the entire structure with steel to accommodate heavier trains. Later that year, about 100 to 150 men, working 10-hour shifts, completed the job in 105 days. The new steel viaduct had the same measurements, but now weighed 6,706,000 pounds.
The Creation of Kinzua Bridge State Park
Freight traffic discontinued during 1959. During 1963, Governor William Scranton signed a law that created Kinzua Bridge State Park. The park officially opened during 1970. Kinzua Viaduct received national recognition when it was placed on the National Register of Historic Civil Engineering Landmarks during 1977.
Beginning during 1987, excursion trains traveled from Marienville, Pa., through the Allegheny National Forest, stopping on Kinzua Viaduct before returning to their point of origin.
During February 2002, DCNR engineers decided the structure needed a full-scale inspection. During June, DCNR barred excursion trains from the bridge. By June, excursion trains were barred from the bridge. During the inspection engineers found sections of steel were rusted through. Then, during August, the bridge was closed to all traffic, including pedestrians.
Engineers determined high winds could create lateral pressure on the bridge, causing it to shift the center of gravity, thus increasing the weight on one side. Such an event could send the whole bridge crashing to the bottom of the Kinzua Creek Valley.
Beginning in February, 2003, W. M. Brode Co. of Newcomerstown, Ohio, a national leader in railroad bridge construction and repair, began working to restore Kinzua Viaduct.
On Monday, July 21, 2003, at approximately 3:15 p.m., an F1 tornado (wind speed 73 – 112 mph) struck the side of Kinzua Viaduct. Eleven towers from the center of the bridge were torn from their concrete bases and thrown to the valley floor.
The Skywalk
Today, park visitors can once again walk a portion of the Kinzua Bridge. Built on six restored, original towers, a pedestrian walkway (skywalk) leads to a 225-foot high observation deck that gives a towering view of the Kinzua Creek Valley.
A partial glass floor in the deck reveals a breathtaking glimpse into the steel structure of the bridge. The 11 twisted and scattered bridge towers blown over by the tornado remain at the bottom of the valley for visitors to view from the deck railings. Several benches line the paved walkway to the skywalk.
A grand opening was held on September 15, 2011.