In July 1863, Union and Confederate forces fought in a three-day battle at Getty

Cemetery Ridge is composed of a dense, resistant basaltic material, so resistant that even though it is geologically older than the dike at Seminary Ridge, it stands higher and steeper in relief. This made it very, very difficult for Confederates to storm, particularly under fire and weighed down with gear. The steepness also made firing uphill accurately difficult for the Confederates. Finally, the basaltic material was so resistant to weathering that some units (particularly those on Little Round Top) built breastworks out of smaller chunks of the material. Reports from soldiers indicate that the lead bullets bounced off the dense rock of the breastworks.