The Bridge of Khazad-dûm and more art by Jay Johnstone

Glamdring the Balrog then leapt onto the bridge, brandishing its whip, and in response Gandalf smote the Bridge before him with his staff.
The staff broke asunder, a blinding sheet of white flame springing up, and the bridge cracked at the feet of the Balrog, who fell forward into the abyss. But as the Balrog fell, it lashed out with its whip, catching Gandalf and dragging him over the edge and into the darkness below.