The Longhai railway (simplified Chinese: 陇海铁路; traditional Chinese: 隴海鐵路) is a major arterial east-west railway in China. It runs from Lianyungang, Jiangsu on the Yellow Sea to Lanzhou, Gansu through the provinces of Jiangsu, Anhui, Henan, Shaanxi, and Gansu, covering a total length of 1,759 kilometres. The line is named after Gansu, also known as Long (陇) in Chinese and Lianyungang's previous name, Haizhou. The Longhai Line is one of the busiest Chinese railways.
Locomotive Nr. 515 was one of three 4-6-2s built for the Lung-Hai Railway by Werkspoor in 1936.