Without a doubt, the single most popular traditional sport in Mongolia is wrestling, and it forms a key part of almost any celebration. (Not that people need an excuse to wrestle - I've often seen young boys or construction workers on break wrestling in the street.) The object is to cause your opponent's knee, elbow or back to touch the ground. Some matches - especially in the early rounds of a naadam competition - are over in seconds. Others can go on for an hour or more.