"A Time for Reflection at the Arlington National Cemetery The Arlington National Cemetery is a 625-acre cemetery where fallen veterans have been laid to rest since the American Civil War. The cemetery lies at the end of Memorial Bridge, across the Potomac River from the Lincoln Memorial in Washington, DC. Wandering among the hundreds of thousands of white headstones is a solemn experience that forces visitors to reflect on the stories and dedication behind each service person. Paid bus tours that depart from the Welcome Center are available for visitors seeking to discover the grounds' rich history. Stops include the Arlington House, Kennedy grave sites, and the Tomb of the Unknown Soldier , where the changing of the guard ritual occurs every hour, on the hour. Those who want to explore the grounds at their own pace or desire to locate a specific grave can download the cemetery's free ANC Explorer app."