The Naval Proving Ground was established in Indian Head in 1890 to test guns, powder fuses, and other naval ordnances and to produce smokeless powder, and it became essential in supplying naval ships during World War I. Harsh winters often limited use of the Potomac River for moving raw materials and finished products, while gravel roads were slow or unusable because of wet conditions and flooding, creating the need for a railroad as European conflict increased supply demands. In 1918, Congress appropriated $800,000 for the project, and brothers Fred and Marshall Bailey won the bid to build a fourteen and one-half mile line connecting Indian Head to the Pennsylvania railroad junction in White Plains. Using thirty local men, the contractor completed the railroad in six months, and in May 1919 it opened for business and played a vital role in the development and operations of the Navy base. The base also became Charles County's largest employer for most of the past century, and during the onset of World War I a footbridge across Mattawoman Creek linked Marbury and Pisgah to the base to speed workers to their jobs. Just before World War II, improved roads and transportation routes made the railroad obsolete, and after decades of disuse the abandoned corridor was donated by the U.S. Navy to Charles County in 2006 through the Department of the Interior's Federal Lands to Parks Program for perpetual public recreational use as the Indian Head Rail Trail, Southern Maryland's first successful rails-to-trails conversion project.