The United States Navy purchased real estate along the Delaware River, establishing the Southwark Yard between Federal and Reed Streets in 1801. The Southwark Yard remained active for much of the nineteenth century. New technology allowing ironclad ships changed the production process, necessitating changes at the Southwark Yard to keep it competitive. Investments in floating dry docks (the first in the world) extended its useful life, but eventually it became clear that Philadelphia would need a new shipyard.

The City of Philadelphia eventually transferred 923-acre League Island to the U.S. Government in 1868. Funding came slowly in the wake of the Civil War, but the first buildings began to rise in the 1870s. After eight years of running two shipyards, Southwark closed in 1876. The Philadelphia Naval Shipyard continued to operate as a naval base until 1996, employing more than 40,000 people during its peak production period in World War II. During that time, fifty-three warships were constructed, and an additional 1,218 were repaired.

The Dravo Wellman Company was a pioneer manufacturer of steel plant equipment with an international reputation for engineering some of the largest material-handling projects ever built. The firm, started in 1896 as the Wellman-Seaver Engineering Company, was founded by the inventor of the first open-hearth furnace in the United States, Samuel T. Wellman (1847-1919), his brother, Charles H. Wellman (1863-1905), and John W. Seaver (1838-1908). Its purpose was to engineer and design steel mills and industrial plant equipment. It was incorporated as the Wellman-Seaver-Morgan Company in 1903 after Thomas R. Morgan (1859-1905) joined the firm. As Wellman-Seaver-Morgan contracted business from all over the world, it concentrated on expanding its material-handling equipment.

In 1954, the Cleveland-based McDowell, Inc., an international construction and engineering firm, acquired Wellman. In 1963, there was an official merger of these two companies, producing the McDowell-Wellman Engineering Company. The Massachusetts firm, Helix Technology Corp., purchased McDowell-Wellman in 1978 and sold its bulk material-handling unit and research center to Pittsburgh's Dravo Corporation.