Rome was set to host the 1908 Olympics when Mount Vesuvius erupted two years prior, forcing the city to forgo the Games due to the cost of rebuilding (although some historians speculate that Italy was struggling to fund the event even before the volcano erupted).

BBC: The ghosts of London's Olympic past

In 1908 London rescued the Olympics after Mount Vesuvius volcano erupted, causing the selected city of Rome to pull out.

CNN: London 2012 legacy: Trust the British to get it right

Gold medals were made of solid gold at three Olympics -- in 1904, 1908 and 1912 -- but the medals themselves were smaller.

CNN: Why Olympians bite their medals