The Kinzua Bridge or the Kinzua Viaduct (/ˈkɪnzuː/[4] or /ˈkɪnzuː.ə/) was a railroad trestle that spanned Kinzua Creek in McKean County in the U.S. state of Pennsylvania. Prior to its collapse in 2003, the bridge was 301 feet (92 m) tall and 2,052 feet (625 m) long.

The bridge was originally built from iron in 1882 and was billed as the “Eighth Wonder of the World”, holding the record as the tallest railroad bridge in the world for two years. In 1900, the bridge was dismantled and simultaneously rebuilt out of steel to allow it to accommodate heavier trains. It stayed in commercial service until 1959 and was sold to the Government of Pennsylvania in 1963, becoming the centerpiece of a state park. Restoration of the bridge began in 2002, but before it was finished, a tornado struck the bridge in 2003, causing a large portion of the bridge to collapse. Corroded anchor bolts holding the bridge to its foundations failed, contributing to the collapse.

Before its collapse, the Kinzua Bridge was ranked as the fourth-tallest railway bridge in the United States. It was listed on the National Register of Historic Places in 1977 and as a National Historic Civil Engineering Landmark in 1982. The ruins of the Kinzua Bridge are in Kinzua Bridge State Park off U.S. Route 6 near the borough of Mount Jewett, Pennsylvania.

http://en.wikipedia.org/wiki/Kinzua_Bridge
http://www.dcnr.state.pa.us/stateparks/findapark/kinzuabridge/