In 1863, Abraham Lincoln stood here and gave the speech that was to become his most famous. With brevity and eloquence he spoke of the liberty and equality upon which this country was founded. He looked forward to the Union's salvation, the end of slavery – and "a new birth of freedom."

What he couldn't have foreseen delivering the Gettysburg Address that afternoon was that a Southern colonel would one day claim this hallowed ground in the form of a KFC just beyond its gates. Or that the site of the battle's largest field hospital would be paved over. Today, a sizable chunk of Camp Letterman serves as the parking lot for Giant supermarket – a salmon slab of concrete with a few benches and two small plaques the only reminder of its historical significance.

Last year activists fought off the unthinkable: a 5,000-slot casino within a mile of the battleground. Yet Gettysburg stubbornly remains on a list of "Endangered Battlefields" compiled annually by the nonprofit Civil War Preservation Trust.

It's not just Gettysburg either. The storied sites pored over in every American History class and obsessively revisited by Civil War buffs are far from uniformly protected. From suburban sprawl to mining to a lack of funds for maintenance and repair, threats to Civil War battlefields are legion.

Many are scrambling to spruce up their grounds in time for the Civil War's 150th anniversary in 2011. Far from being diminished through the years, the significance of these battlegrounds, as a sort of collective time capsule, has only grown.