English: DAYTON, Ohio -- Chinese stone roller on display in the Air Power Gallery at the National Museum of the United States Air Force. (U.S. Air Force photo)

During World War II, the United States and China forged a strong friendship based on mutual strategic interests and shared sacrifice in fighting and defeating Japan in the Pacific theatre. A key Chinese contribution involved the use of thousands of workers and hand-hewn stone rollers to construct airfields throughout China to support Allied offensive air operations and the airlift of vital supplies into China.

Weighing approximately 10,000 pounds, the stone roller on display aided in the construction and maintenance of the central Cheng Gong airfield in Kunming. One hundred workers normally pulled the stone rollers back and forth on mile-long runways to compress earth and rock, smoothing the runways for use by 14th Air Force fighters and bombers as well as transport aircraft flying the "Hump Route" over the Himalayas from India to China.

Heavy equipment and fuel were not available for airfield construction as Japanese military successes isolated China from conventional land and sea supply routes. Airlift over the Himalaya Mountains proved the only available option of supplying China. Using only hand tools, thousands of Chinese workers constructed hundreds of air bases and airfields. These hand-made runways normally measured 5,000 to 7,000 feet long, 150 feet wide and up to five feet thick.

The airfields constructed by the Chinese people proved to be a critical factor in the success of the U.S. air campaign against Japanese forces. The simple stone rollers stand today as symbols of Chinese determination, toil and sacrifice in resisting Japanese aggression and in defending freedom.

The stone roller was donated by the Citizens of Yunnan Province, Peoples' Republic of China, in 2004.