The Keystone Cup is the Junior "B" ice hockey championship and trophy for Western Canada. The championship is the culmination of the champions of 12 hockey leagues in British Columbia, Alberta, Saskatchewan, Manitoba, and Northwestern Ontario.
The Keystone Cup got its name from the Keystone Centre in Brandon, Manitoba. The original tournament took place in 1983 in Portage la Prairie, Manitoba and was won by the Selkirk Fishermen of the Manitoba Junior B Hockey League. The alternate arena at the tournament was the Keystone Centre and the trophy awarded to the championship was nicknamed after it.
The championship is determined through a round robin of the winner of the Cyclone Taylor Cup in British Columbia, the winner of the Russ Barnes Trophy in Alberta, the winner of the Athol Murray Trophy in Saskatchewan, the Keystone Junior Hockey League, and the William Ryan Trophy in Northwestern Ontario.
In previous years, the winner of the Keystone Jr. B League would have had to go through the Manitoba Provincial Junior B Hockey Championship, but in 2004 their only competition, the Northwest Junior Hockey League, folded. The same thing happened in the William Ryan Trophy Championship for the Thunder Bay Junior B League, as their only competition, the North of Superior Junior B Hockey League, folded in 2004.