Both survived the fall, and Gandalf pursued the Balrog for eight days through the deepest caverns beneath Moria. At last they came to the Endless Stair, and climbed the steps that led to the peak of Zirakzigil. There Durin's Bane fought its last battle - for two days and nights, the Balrog battled with Gandalf, but at last it was cast from the peak, and broke the mountain-side as it plunged to its doom.