 Today, most former D&RGW main lines are owned and operated by the Union Pacific while several branch lines are now operated as heritage railways by various companies.The Denver & Rio Grande Railway (D&RG) was incorporated on October 27, 1870 by General William Jackson Palmer (1836-1909), and a board of four directors.It was originally announced that the new railroad would proceed south from Denver and travel an estimated south to El Paso via Pueblo, westward along the Arkansas River, and continue southward through the San Luis Valley of Colorado toward the Rio Grande.