1912: The Stockholm Olympics saw two epic struggles in Greco-Roman wrestling. In the light heavyweight final, officials declared a draw after Anders Ahlgren of Sweden and Ivar Böling of Finland had tussled for nine hours. In the semi-final of the middleweight division, Martin Klein of Russia triumphed over Alfred Asikainen of Finland after 11 hours, but was too weary to contest the final.
Source: David Wallechinsky, The Complete Book of the Olympics (2004), pp. 673, 686