Twenty-one steps : guarding the tomb of the unknown soldier
(Book)

"Keeping vigil at the Tomb of the Unknown Soldier, in Arlington National Cemetery, are the sentinel guards, whose every step, every turn, honors and remembers America's fallen. They protect fellow soldiers who have paid the ultimate sacrifice, making sure they are never alone. To stand there--with absolute precision, in every type of weather, at every moment of the day, one in a line uninterrupted since midnight July 2, 1937--is the ultimate privilege and the most difficult post to earn in the army. Everything these men and women do is in service to the Unknowns. Their standard is perfection. Exactly how the unnamed men came to be entombed at Arlington, and exactly how their fellow soldiers have come to keep vigil over them, is a sobering and powerful tale, told by Jeff Gottesfeld and luminously illustrated by Matt Tavares--a tale that honors the soldiers who honor the fallen."--Amazon.