Last of the Steam-Powered Trains (IMAGE) University of Kansas Caption The Union Pacific Big Boy Steam Engine (one of the largest steam engines ever built and still functioning) visited Lawrence, Kansas, on Sept. 2, 2021. Credit Bruce Lieberman Usage Restrictions None License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.