The Crater at Petersburg

By the time grant had laid siege to Petersburg, Lee's army had become greatly weakened after 4 years of fighting. His fighting force in Petersburg only numbered around 50,000 troops. In attempts to break the siege, General John Gordon led an assault of 12,000 men on fort Stedman. Though the confederacy succesfully took the fort, heavy union artillery was inflict many casualties and drive the confederates back out of the fort. Both sides began to dig trenches and became reluctant to go on the offensive. General Burnside and his men concocted the idea of digging a tunnel under the confederate position and filling it with explosives to create a breach in the confederate lines that could be exploited by Union infantry. After weeks of preparation, Burnside was ready to light the fuse and
create what is known as the battle of the crater.





On July 30th, a position in the confederate defenses was blown and unit after unit of union soldiers charged. Going into the crater, the charge was stopped. In mass confusion, General Mahone gathered as many men as he could and launched a counter attack. They surrounded the crater and began firing down into it.  Some Union troops managed to flank to the right of the crater and assault the confederate lines, driving them back, but the confederates had managed to repel the Federal troops and drove them East.




https://en.wikipedia.org/wiki/Battle_of_the_Crater#Battle
https://www.battlefields.org/learn/civil-war/battles/crater
https://en.wikipedia.org/wiki/Siege_of_Petersburg