(Photo courtesy of Kansas State Historical Society)

It is of Navajo railroaders in Barstow in 1950s.

The expansion of the railroad to the Western half of the United States was an important development in our country’s history. And, to do that, someone had to build it.

A new documentary, "Metal Road," explores the Navajo people’s important role in this industry and its long history. Filmmaker Sarah Del Seronde talked about the documentary.