In 2014 - in the episode 5.04 The End - Dean, escaping the Croatoan virus zone that is Kansas City, goes looking for Bobby Singer, but finds his house deserted. In a hidden drawer, he finds Bobby's journal, in which he discovers a picture of Bobby, Castiel and a few other unknown people, decked out in survival and hunting gear at a place called Camp Chitaqua.
Dean goes looking for the camp shown in the picture, and finds the Impala rotting away. The camp is a haven for survivors of the Croatoan virus, and also a base for the operations of Future!Dean. Future!Castiel is also there, although minus his angelic powers he spends most of his time stoned. In contrast Future!Chuck is organised, and in charge of supplies.