Wild commanded 1,100 men and two cannons. The Union force consisted of the 1st USCT and four companies of the 10th USCT. Battery M, 3rd New York Artillery was the only all-white unit in the defenses. The gunboat USS "Dawn" lay in the James River to deliver fire support to the fort's defenders. The fort was crescent-shaped facing north, about long, straddling the road to the wharf. It was anchored on both ends—to the west on a bluff and on the east by a branch of Kennon Creek—so it could not be flanked. It was fronted by a deep, broad ditch and abatis.