Artist Alfred Waud sketched the Union infantry assault on The Crater at approximately 8 a.m. on Saturday, July 30, 1864. As Union troops rush into the forward trenches (foreground) to reinforce the attack, other Union soldiers climb up the mounded earth left after 4 tons of gunpowder blew a huge hole in the forward Confederate defenses. Beyond The Crater spreads the high ground upon which the Confederate secondary defenses were located; if they had attacked those defenses as expected, Union troops could have shattered the enemy lines and marched into Petersburg, Va. This image was published in the in Aug. 22, 1864 Harper's Weekly.