Battle of the Crater - Lee Defeats Burnside

The Battle of the Crater was a battle of the American Civil War, part of the Siege of Petersburg. It took place on July 30, 1864, between the Confederate Army of Northern Virginia, commanded by General Robert E. Lee and the Union Army of the Potomac, commanded by Maj. Gen. George G. Meade (under the direct supervision of the general-in-chief, Lt. Gen. Ulysses S. Grant).

After weeks of preparation, on July 30 the Federals exploded a mine in Maj. Gen. Ambrose E. Burnside's IX Corps sector, blowing a gap in the Confederate defenses of Petersburg, Virginia. From this propitious beginning, everything deteriorated rapidly for the Union attackers. Unit after unit charged into and around the crater, where soldiers milled in confusion. The Confederates quickly recovered and launched several counterattacks led by Brig. Gen. William Mahone. The break was sealed off, and the Federals were repulsed with severe casualties. Brig. Gen. Edward Ferrero's division of black soldiers was badly mauled. This may have been Grant's best chance to end the Siege of Petersburg. Instead, the soldiers settled in for another eight months of trench warfare. Burnside was relieved of command for his role in the debacle.

http://en.wikipedia.org/wiki/Battle_of_the_Crater