A bridge laying device (2) for laying a bridge (3), in particular a single-piece bridge, includes a main part (5) for arranging on a load transport vehicle (7), in particular a hook-lift vehicle, a laying arm (12) for setting down the bridge (3), and an extending device (6) for moving the laying arm (12) from a transport position into an extended placing position. In certain embodiments, a bridge laying system (1) includes a load transport vehicle (7), in particular a hook-lift vehicle, and a bridge laying device, (2) which can be arranged on the load transport vehicle (7). A method for laying a bridge (3), in particular a single-piece bridge, using a bridge laying device (2) includes moving an extending device (6) for moving the laying arm (12) from a transport position into an extended placing position.