"'Rock Island Trail' tells a story of the building of the first bridge and railroad over the Mississippi River from Rock Island, Illinois, to Davenport, Iowa. The World Premier of the film was in the Quad Cities, USA, on April 27th, 1950. Republic stars took part in a pre-show promotional parade which extended from Silvis, Illinois, the Home Yard of the mighty Rock Island Lines, at the time the largest rail yard in the world, to the theater in Rock Island, Illinois, and included John Wayne, Roy Rogers, Dale Evans and Rock Island Railroad employees.