Beginning in 1892 with the establishment of the Bear Creek Refining Company in Marcus Hook, the refining industry became a major influence on the Delaware River and its riverfront communities. The area's access to road, rail, and deep-water port facilities, along with an extensive pipeline infrastructure, continued to draw the industry there. The refinery in Trainer began operation in 1900 when the Union Petroleum Company leased a 17-acre tract from the Reading Company railroad. The first refinery there, built primarily of wood, burned in 1912, was quickly rebuilt, and four years later Union bought the land from the railroad along with an additional 242 acres. Sinclair Oil Corporation purchased the Trainer refinery in 1925, when production was 10,000 barrels per day, and operated it for more than 40 years. Ownership later passed to British Petroleum in 1969, Tosco Corporation in 1995, Phillips Petroleum Co., later ConocoPhillips, in 2001, and Monroe Energy, a subsidiary of Delta Airlines, in 2012, after which it continued producing high-grade airline fuel and other petroleum products. The Sun Oil Co. refinery in Marcus Hook has operated since 1901, growing from an 82-acre site into a larger complex that included laboratories and a research and development facility. Major advances in petroleum production were developed there, including the Houdry Process of catalytic refining in 1937, which produced high-grade aircraft fuel and increased the yield of each barrel of crude. The airline fuel produced there is credited with giving the U.S. an advantage in the air during World War II.