The Olympic Games are held every four years in tribute to their ancient origins. The original Olympics were held at Olympia every four years. During this period, the passing of time was marked by "Olympiads," which refers to the four-year span between Games.
According to historic manuscripts, the ancient Olympic Games were held every four years in Olympia from 776 B.C. until A.D. 393. The plan to recreate the Olympic Games was introduced in 1894, and the International Olympic Committee was formed. In 1896, the first modern Olympics were held in Athens. In 1924, the first Olympic Winter Games were held in France. Between 1924 and 1992, the Summer and Winter Games were held in the same years. In 1986, the IOC resolved to hold the Winter Games in four year intervals that were two years after the Summer Games. The first Winter Games on the new cycle were held in 1994 in Lillehammer, Norway.
As of 2014, since the inception of the modern Olympic Games, 22 different cities have hosted 27 Summer Games, and 19 different cities have hosted 22 Winter Games. Due to war, three Summer Games and two Winter Games have been cancelled. Rio de Janeiro is due to become the first South American host city in 2016, at which point, Africa will be the only continent not to have hosted a modern Olympics.