The Lieutenant who leaves the tunnel at the beginning of this episode is the same one who escapes from "Camp 13" in the very first episode and changes places with Carter. Hogan called him their "outside man".
Two of the (uncredited) German guards seen in the background behind Colonel Klink appear as camp guards in several other episodes. In a later episode, these same two appear as Gestapo storm troopers.
The license plate on Max's mail delivery truck is WH 66042.
When Sergeant Franks is drilling (marching) the prisoners, he is shouting, "eins zwei, eins zwei, eins zwei" which is one two, one two, one two, in the German language.