Short by catalog standards, often four to ten weeks, because entry is cheap and decisions are late. The binding constraint is not entry but accommodation: these events are frequently held in small towns whose entire hotel stock is consumed by the tournament, which means the real deadline is months before the entry deadline.
Club nights, league matches, analysis after the game which is often longer than the game, online play that maintains the relationships between events, and in bridge, a partnership that functions as a small marriage. The long-established summer opens that occupy the same fortnight annually in the same small European towns, the winter opens in the Mediterranean, the biennial team olympiad, the October board-game fair in Germany which is the largest single gathering in this row, and the summer American convention.
July and August, when the European open circuit runs continuously and players chain two or three events into a month of travel.