1908 London Olympics
Also called: Games of the IV Olympiad, London 1908
London stepped in when Rome withdrew after the eruption of Vesuvius. Teams marched in by nation, and the 42.195 km marathon distance dates from these Games.

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Rome was the original host, but after Vesuvius erupted in 1906 Italy withdrew and London took over. The Games ran from 27 April to 31 October 1908, with some 2,000 athletes from 22 nations. At the purpose-built White City Stadium, teams paraded by nation behind their flags.
The marathon was set to run from Windsor Castle to the royal box in the stadium, making it 42.195 km, which became the official marathon distance in 1921. Italy’s Dorando Pietri entered the stadium first but collapsed and was helped across the line by officials, so he was disqualified; Queen Alexandra presented him with a silver cup of his own.