Chengdu-Kunming Railway Ivory Carving. China presented the carving to the United Nations in 1974. Connecting Southwest China's Yunnan province and Sichuan province with more than 1,000 kilometers of line, the railway opened to traffic in 1970. The carving from eight elephant tusks reportedly took 98 artisans more than two years to craft. The sculpture is so intricate that the train includes tiny people.