https://theplayersaid.com/2026/06/25/history-behind-the-cards-a-look-at-checkpoint-charlie-from-gmt-games-card-card-1-cousins-operation/The Players' Aiden2026-06-25T12:00:00+00:00History Behind the Cards – A Look at Checkpoint Charlie from GMT Games – Card #1: Cousins OperationGMT, GMT Games, P500, Cold War, wargame, Berlin, 1945, Wargame Wednesday, Event Card, West Germany, History Behind the Cards, Card #1, CIA, Central Intelligence Agency, Checkpoint Charlie, SIS, Russell Brown, 1960's, Cousins Operation, British SIS, Secret Intelligence Service, Potsdam Agreement, British-US Communications Intelligence Agreement, BRUSA, UKUSA, Five Eyes, KGB, CIA Operation, KGB Agenthttps://theplayersaid.com/wp-content/uploads/2026/06/checkpoint-charlie-history-behind-the-cards-header-2-e1782395360567.png?w=150