Distance from Baltimore: 70 miles, about an hour-and-a-half drive

Why it's worth the gas: More than 100,000 Union and Confederate soldiers met on Sept. 17, 1862, in a battle that produced 23,000 casualties. A century and a half later, you can imagine the roar of cannon and guns as you pass through peaceful meadows and over Burnside's Bridge. Thousands of acres showcase weapons, memorials, graves and structures that together tell the story of the bloodiest day of the Civil War. Films and displays at the Visitor's Center describe how factors in the fight -- such as dumb luck and squandered opportunities -- kept either side from a decisive victory, yet the result emboldened President Abraham Lincoln to issue the Emancipation Proclamation.

Don't miss: The 150th anniversary of the battle will be marked Sept. 15-17 with tours, hikes, lectures, music and children's activities. The names of soldiers killed or gravely wounded will be read at a remembrance ceremony Sept. 17.

Information: Antietam National Battlefield, 5831 Dunker Church Road, Sharpsburg, Md., 21782; 301-432-7648 or nps.gov/ancm.