07/21/2015 10:13 AM EDT
On this day in 1861, the first major battle of the Civil War – the First Battle of Bull Run – unfolded on the slopes of Henry Hill and Matthews Hill. Also know as the Battle of First Manassas, Bull Run taught both the North and South that the war would not be a short affair, settled through one decisive and epic battle. Today the Manassas National Battlefield Park provides visitors the opportunity to learn about the Civil War through historic sites, walking trails ranger-led programs. National Park Service Photo.