A Texas border town is working to restore what is believed to be the only remaining site that once helped process the millions of Mexicans who came to the U.S. as temporary guest workers under a program that started during World War II.

The crumbling white adobe buildings at Rio Vista Farm in Socorro, a town along the Rio Grande about 620 miles west of Dallas, were the arrival point for “braceros” — Spanish for laborers — who came to the U.S. to work on farms and railroads as part of a program in the middle part of the 20th century. Local officials and preservationists hope to turn it into a site that will tell the story of the workers and a largely forgotten program that lasted for about 20 years.