 Complete the following phrase:  In the early history of hockey, games were played outdoors on rivers, lakes, and other naturally occurring ice surfaces. In fact, the first indoor game, held in 1875, was a novelty at the time, yet after that the game moved inside. While the first Olympic hockey tournament, held in 1920, was played indoors, games at the first Winter Olympics in 1924 were the first of several such tournaments to be played outdoors. Games at the World Championships were occasionally played outdoors, including the 