"We are incredibly proud of what we do," he says.

Tilley and the other sentinels guard the tomb every hour of the day, every day of the year.

U.S. Army

One of the sentinels guarding the Tomb of the Unknowns at Arlington National Cemetery.

"Since 1937 we've never left our post, and that's in every type of weather you can imagine," he says.

Even when Hurricane Isabel was bearing down on the area, in 2003, the sentinels stood their ground.

"They gave the option to leave our post, and the sentinels honorably declined," Tilley says.

That was the only time the sentinels were given that choice. They live by their Sentinel Creed, which states in part, "My standard will remain perfection."

Honor in the details
That perfection is reflected in the way they guard the Tomb of the Unknowns. They walk exactly 21 steps, pivot, wait 21 seconds and retrace their 21 steps for as long as two hours at a time.

"Twenty-one is the highest honor that you can give to the military – the 21-gun salute," Tilley explains. "Everything we do here is off the count of 21."

Another example of their perfection is their spotless appearance. The sentinels spend four to six hours each day just shining their shoes between guard walks.

"That's one pair of shoes," Tilley says. "To get a brand new pair of shoes ready to go takes about 40 to 50 hours."

New shoes are sanded down to eliminate their texture and then re-shined. A power sander is used to sand down the soles of the shoes, which also are shined again.

"We shine, shine, shine and sand down the shine, get all the texture out and start shining them back up," Tilley says. "It's just a long, long process."

A somber place
Tilley tells how veterans often come and sit on the steps overlooking the tomb.

U.S. Army

Spc. John Tilley, one of the guards at the Tomb of the Unknowns at Arlington National Cemetery.

"You can tell there's just a very somber mood about them as they watch us, and some even shed tears," he says. "We're very humbled when they come."

Unlike many soldiers, Tilley, who's 26 and single, didn't have a burning desire to be in the military. He grew up in Statesville, N.C., and graduated from Western Carolina University with a degree in history. He spent a year in a seminary before deciding to join the Army in 2006.

"I was young and fit and wanted to serve my country," he says.

Tilley was selected for the Old Guard and volunteered to be a sentinel at the Tomb of the Unknowns.

"We know we are part of something really special," he says.

He hopes one day to go to Officer Candidate School and become either an infantry officer or a helicopter pilot.

"I'm kind of itching to get in the fight overseas," he adds.

Until then, he'll continue as a sentinel at the Tomb of the Unknowns, completing his 1,000th guard walk before leaving on his next assignment in about a year.

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