Revealing mistake: When the Remagen bridge is bombed, it is obvious that the bomber planes shown have been taken from several shots (possibly also from an earlier film) and the shots were superimposed. Also, the bombers appear transparent, and the background sky's color is unnaturally strong, too.
Continuity mistake: In this scene we see the General briefing his men. A map is spread out over the bonnet of a jeep. While he is studying the map and planning the next move a steaming hot cup of something is given to the General and is placed on the map for him. The General then takes it in his right hand and is about to drink it when someone speaks to him. The General replies to him and in the next wide angle shot there is no cup in his hand nor is it anywhere else.