From the record
“The State Highway 79 Bridge at the Red River was a bridge carrying Texas State Highway 79 and Oklahoma State Highway 79 over the Red River at the Texas-Oklahoma state line. The camelback pony truss bridge was 2,255 feet (687 m) long and had 21 truss spans.”
Wikipedia article State Highway 79 Bridge at the Red River, CC BY-SA 4.0.
One of 3 National Register listings published here for Clay County · listed in 1996 · category: Structure.
Sources: the Wikipedia article · the case file at the National Archives · the National Register database, National Park Service