Baldwin Locomotive Works was an American manufacturer of locomotives, founded in 1825 in Philadelphia, Pennsylvania. It became one of the largest and most prominent locomotive builders in the United States, producing thousands of steam and diesel locomotives over its long history. The company played a significant role in the expansion of the American railway system during the 19th and early 20th centuries. The company was known for its innovative designs and engineering excellence, contributing to the development of various types of locomotives, including steam locomotives and diesel-electric locomotives. Baldwin Locomotive Works ceased production in 1956, but its legacy continues to influence the railway industry today.