Please describe the Battle of Gettysburg in the American Civil War?

The goal of General Robert E. Lee and his Army of Northern
Virginia was to take the action from war-torn Virginia onto Northern soil. Fresh off the
electrifying victory at Chancellorsville (where his heavily outnumbered army had been
caught off-guard), Lee's army was at its peak and probably the greatest fighting force
in the world. Lee's confidence (which proved to be overconfidence) in his troops was
also high, and his grand plan was to resupply his troops from the plentiful farmlands of
Pennsylvania while marching toward Baltimore and Philadelphia. His hope was to
eventually march southward back toward Washington in the hopes of capturing the capital.
Such a feat would have possibly gained the international recognition from other
nations that would have resulted in financial (and possibly military) aid as well as
formal recognition as a nation. A series of triumphs could also have ended the
war.

However, the vanguard of Lee's troops was surprised in
Gettysburg, and Lee was forced to battle the Union forces there. A series of mistakes
from his new corps commanders, particularly Lieutenant General Dick Ewell (the late
Stonewall Jackson's replacement) on the first day, gave the Federals a solid position to
give battle. Lee's army was unable to dislodge the Union troops from their strong
positions on the second day, and Lee ordered the disastrous "Pickett's Charge" on the
third day.

Although casualties were incredibly high on both
sides, Lee's army was shattered, and he was lucky to return to the safety of Virginia
soil. His losses were unable to be replaced, whereas the Union had vast numbers of men
to reinforce their ranks. Confederate hopes for international recognition and a possible
end to the war were ended, and Gettysburg proved to be the turning point of the war. U.
S. Grant was soon named supreme commander of Union forces, and he took a more aggressive
approach against Lee, who was put on the defensive for the remainder of the
war.