Originally held at Olympia in Greece between the 8th century BC and the 4th century AD, the Olympic Games returned in 1896 after a 1500 year hiatus. A few sports have been featured on every occasion since then, others have slipped into obscurity, some have found a new home within the Winter Olympics, and more continue to be introduced. One thing hasn't changed though, the colour of that elusive medal presented to the champion.