A reenactor portraying a Union soldier in the Murray's Brigade participates during ongoing activities commemorating the 150th anniversary of the Battle of Gettysburg, Thursday, June 27, 2013, at Bushey Farm in Gettysburg, Pa. Union forces turned away a Confederate advance in the pivotal battle of the Civil War fought July 1-3, 1863, which was also the war�s bloodiest conflict with more than 51,000 casualties. (AP Photo/Matt Rourke)
Why did Gen. Robert E. Lee order the ill-fated attack on Little Round Top during the Battle of Gettysburg?
Historians have long wrestled with that question, and now a geographer has come up with an answer, using sophisticated mapping software to re-create the battlefield exactly as Lee saw it.
The explanation: Lee simply couldn't see many of the Union soldiers amid the hills and valleys. As a result, the Confederate general underestimated his enemy's troop strength.
That's the conclusion of Middlebury College professor Anne Knowles, who oversaw the development of the map for the Smithsonian Institution to mark Gettysburg's 150th anniversary next week.
The panoramic map went live on the Smithsonian website Friday.
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