 It went into camp at Hall's Hill, Arlington, Virginia, Defences of Washington, D.C., for the winter of 1861-62.At the Battle of Gettysburg on the second day they defended Little Round Top against a determined Confederate attack aimed at flanking the Union Army.They were one of four regiments, of the 3rd brigade, of the 1st Division of the V Corps of the Union Army of the Potomac.