Arlington National Cemetery is the resting place of more than 400,000 American military veterans, spread across 253 hectares on the Virginia side of the Potomac. It is an active cemetery — funerals take place every weekday — and the scale and solemnity are difficult to prepare for.
The Tomb of the Unknown Soldier is the most visited spot: a white marble tomb with a continuous 24-hour guard, changed every 30 minutes in summer. The changing of the guard ceremony is precise and worth watching. President Kennedy's grave, marked by an eternal flame, is nearby on the slope below the Lee mansion. Trolley tours are available for those who can't walk the grounds.