Tenbridge is a vertical-lift railroad

Rail transport

Rail transport is a means of conveyance of passengers and goods by way of wheeled vehicles running on rail tracks. In contrast to road transport, where vehicles merely run on a prepared surface, rail vehicles are also directionally guided by the tracks they run on...

 bridge over the Tennessee River

Tennessee River

The Tennessee River is the largest tributary of the Ohio River. It is approximately 652 miles long and is located in the southeastern United States in the Tennessee Valley. The river was once popularly known as the Cherokee River, among other names...

. It has a main span of 310 feet (94.5 m), and is one of the longest vertical lift spans in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

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The original span was a swing span with a center pivot that was originally built in ca. 1879/1880. It was replaced by a vertical lift span in 1917, but the lift towers and machinery were not installed until 1920. It remains a very busy crossing on the Cincinnati, New Orleans and Texas Pacific Railway

Cincinnati, New Orleans and Texas Pacific Railway

The Cincinnati, New Orleans and Texas Pacific Railway is a railroad that runs from Cincinnati, Ohio, south to Chattanooga, Tennessee, forming part of the Norfolk Southern Railway system. The rail line that it operates, the Cincinnati Southern Railway, is owned by the City of Cincinnati and is...

, a major subsidiary of the Norfolk Southern Railway

Norfolk Southern Railway

The Norfolk Southern Railway is a Class I railroad in the United States, owned by the Norfolk Southern Corporation. With headquarters in Norfolk, Virginia, the company operates 21,500 route miles in 22 eastern states, the District of Columbia and the province of Ontario, Canada...

. The bridge carries two mainline tracks across the river.

The bridge is one of only three known nesting locations in Tennessee

Tennessee

Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...

 for Peregrine Falcon

Peregrine Falcon

The Peregrine Falcon , also known as the Peregrine, and historically as the Duck Hawk in North America, is a widespread bird of prey in the family Falconidae. A large, crow-sized falcon, it has a blue-gray back, barred white underparts, and a black head and "moustache"...

, a Tennessee and Federal Endangered species

Endangered species

An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

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