Washington lies at the center of dark and bloody ground. Within four hours by car are the battlefields where the United States won its independence, where we were shamed in our only invasion by a foreign power, where the flame of Southern separatism burned brightest, and where it dwindled and died.

We tend to think of our foreign wars on Memorial Day because of the warriors still among us. Some few veterans -- and their widows and orphans -- remain from the Spanish-American War and "The Great War," and millions more from World War II, Korea and Vietnam.

We have no living links with the Revolutionary War, the War of 1812 or the Civil War, which to many Americans are no more than vague dates and half-remembered passages from tiresome textbooks. Yet the agony of those conflicts was real, and their consequences affect the life of every American every day: If the Revolution made us independent, 1812 taught us we could not avoid the dangers and duties of sovereignty; and the Civil War transformed us from a squabbling agrarian federation into an indivisible industrial nation and rising world power.

Even the best description of a battle cannot compare with going over the ground, and many of the areas of action around the national capital are preserved or restored so that they present much the same scenes the soldiers saw when they came onto the field.

Most of the battlefields can be toured by car, but take advantage of the long weekend -- and the excellent map- brochures available at the National Park Service visitor centers -- and walk or bicycle over the ground (most principal points can also be reached by wheelchair). Films and exhibits give the outlines of the action and its importance; since the campaigns followed routes that now are highways, it's easy and logical to visit the sites in sequence, such as Second Manassas/South Mountain/Antietam. As you zip along, give a thought to the troops, often barefoot and half-starved, who marched those weary ways.

At some parks there are inexpensive commercial tours, but don't expect the guides to know much beyond the rote spiel, which usually is taped. Each major battle and campaign has inspired excellent books and pamphlets, many of which are for sale at the visitor centers.