A new YouTube series, “Behind the Old Guard,” showcases some of the specialty units within the 3rd U.S. Infantry Regiment. The series’ first video takes an in-depth look at the lengthy application and testing process volunteers undergo before they can become Sentinels at the Tomb of the Unknown Soldier at Arlington National Cemetery.

The Regiment posted the first video, titled “Behind the Old Guard- Sentinels,” on November 28th. Just over ten minutes long, the short program shows interviews with current Sentinels about their testing, training, and experience as the Tomb of the Unknown Soldier’s official guards.

Each a volunteer, these men must adhere to the strictest standards of honor, dignity, and dedication. Because of these high standards and the rigorous selection process, the Tomb Guard identification badge is the second least-awarded identification badge in the United States Army. The Army Astronaut badge is the least awarded identification badge.

The Tomb of the Unknown Soldier attracts millions of visitors each year. The Sentinels have continuously guarded the Tomb 24-hours a day, 7 days a week, and every day of the year for the past 77 years.