To halt Grant’s push towards Richmond, the Confederates constructed a line of breastworks overlooking Totopotomoy Creek. The Federals launched probing attacks on May 29 and 30 as other Union elements crossed the creek to the east, to strike Lee's army from the flank near Bethesda Church. Despite the strong Rebel position, Lee feared that Grant could wrap around his position, and the Confederate and Union lines slowly moved south to Cold Harbor on May 31.