The defenders were ready for the Union men to scale the walls and killed or wounded many of the first attackers as they came to the top of the parapet. Eventually, Union soldiers found the uncompleted short trench in back of the fort which allowed them an easier opportunity to climb onto the fort's parapet. The mass of men in the ditch had to move or be killed so they started to scale the walls and rushed around the moat to find the unfinished trench or sally port in the rear. Soon the flags of the 12th West Virginia Infantry Regiment and 39th Illinois Infantry Regiment reached the top of the walls, inspiring more men to follow.