Complex sentence: First held in Wengen, Switzerland in 1922, it is the oldest student snowsports event and two years older than the Winter Olympic Games, and with 3,200 participants in 2011 it is also billed as the world's largest.
Split into simpler sentences: First held in Wengen, Switzerland in 1922, it is the oldest student snowsports event as well as being two years older than the Winter Olympic Games,. Having taken 3,200 participants in 2011, it is also billed as the world's largest.