For four years, Yvonne Morris worked at Missile Site 571-7. Literally, it was a real hell hole.

Deep underground in a high-security control room, she and her crew held the keys to an apocalyptic hammer -- a nuclear rocket that could flatten an entire city in just 30 minutes.

"I know I would have been able to launch, if ordered," said Morris, an ex-Air Force lieutenant. "But if we launched, then life as we know it was over."

Based near Tucson, Ariz., during the 1980s, Morris joined thousands of steely-eyed missile-men and women who helped bring a peaceful end to the Cold War.

The silo -- now the Titan Missile Museum -- is one of hundreds of American travel destinations that honor the nation's history of military readiness and sacrifice.

How about a fire-spewing WWII battle re-enactment with an actual flamethrower? Or a massive warship that saved 3,000 refugees? Or a training ground for some of the toughest fighting men and women in the world?

Titan Missile Museum

Of all these magnets for the military enthusiast, one thing sets the Titan museum apart: It's the world's only remaining underground installation housing an actual Titan II missile.

"It's not a mockup," says Morris, who's now the museum director. "It's the real deal. Except," she laughs "there's no warhead."

That's probably a good thing, because the Titan II carried the nation's deadliest nuclear warhead -- equal to more than 9 million tons of dynamite.

During its heyday from the 1960s into the 1980s, more than 50 Titan II launch sites dotted Arizona, Kansas and Arkansas. Decades after the Cold War, enthusiasts can now snuggle up close and cozy with a doomsday device.

A special observation deck at the museum allows a breathtaking view of the rocket from tip to tail.

HGTV addicts take note: The underground bunker is designed to rock and roll.

Literally, because the whole complex is cushioned by giant springs.

The floors are separate from the walls so the facility can survive giant shock waves from, say, an earthquake, or perhaps an enemy nuclear missile attack. Careful! When you step into a room, don't trip over the 11-inch gap in the floor. That's called the "rattle space."

Oh, and it's not every day that you can see humongous steel blast doors weighing 3 tons. Don't forget to shut the door behind you on the way out.

On the whole, life in the hole wasn't bad, to hear Morris tell it. Several four-person crews each rotated 24-hour work shifts in the underground habitat. Surprisingly, it was hard to get bored, she said, because they just "drilled and drilled and drilled." Performing equipment maintenance, testing circuits and systems and monthly training, testing and evaluation.

A quarter century after the site was decommissioned, it still holds secrets. We still don't know exactly where the missile was pointed. That's classified.

Did the missile site ever come close to launching? Also classified.

Those untold secrets are shared by the launch crews and their chains of command. We'll likely never know.

U.S. and Soviet nuclear missiles pointing at each other created fear of total annihilation on both sides, historians say, helping to prevent either country from attacking first and starting WWIII. Air Force missile crews played a vital link in that strategy.

"I guess unsung hero is a way to talk about the folks who served during the Cold War," says Morris. "In the next 20 years, as more documents are declassified, we're going to really appreciate more about what went on."

WWII comes to Texas

In Fredericksburg, Texas, volunteers bring World War II battles to life. Firing spectacular Hollywood pyrotechnics and authentic weapons, they re-enact a 10-minute battle where U.S Marines capture a Japanese-held beachhead.

"We can't re-create what war was like," says Brandon Vinyard of the National Museum of the Pacific War. "But this gives people a little bit more of a sense of the chaos of battle."

With plenty of safety precautions in place, visitors enjoy a close view from about 8 feet from the beachhead, Vinyard said. Battle highlights include three huge explosions -- one equaling three sticks of dynamite -- and a star burst that shoots 50 feet high.

There's also a spectacular demonstration of a flamethrower -- a portable blowtorch weapon used to wipe out pockets of enemy resistance.

"If you're in the bleachers you can actually feel the heat of the flamethrower," says Vinyard. "And you can feel the concussion of some of the explosions."

No other facility in the nation does anything like this on this scale on a regular basis, says Vinyard.

It bills itself as the only museum entirely dedicated to telling the story of WWII in the Pacific.

About a year ago a former U.S. Marine and his young grandson found themselves walking through the museum gallery when the veteran came upon a giant mural of a vintage photo on the wall. The picture showed a group of Marines catching a breather on a hillside, remembers Vinyard. "The veteran pointed to one of the young Marines in the photo and said to his grandson, 'That's me. This is where we were.'"

Vinyard's story exemplifies the museum's mission, he said, "to inspire our youth by honoring our heroes."

Witnessing a 'transformation'

This Friday on a parade ground on a marshy barrier island off South Carolina, bands will play, Marines will march, the American flag will fly high, and a commanding general will speak.

Senior drill instructors will dismiss their platoons and hundreds of new graduates will shout, "aye aye sir!" or "aye aye ma'am!"

The drill instructors will then sheath their swords and march away.

With that -- Parris Island marks the end of another spectacular graduation ceremony and a fresh beginning for hundreds of new Marines.

Since it opened in 1915, the U.S. Marine Depot at Parris Island, South Carolina, has become legendary through movies, songs and novels. It has also produced hundreds of thousands of fighting men and women. Military enthusiasts often join family members and other loved ones who visit "The Depot" to enjoy graduation ceremonies -- an unspoiled piece of Americana that's been largely unchanged for almost a century.

Oh, one ceremony modification worth noting: In the 1920s, a dog entered the picture. Marines adopted a canine mascot after German soldiers began referring to the hard-fighting Marines as "Devil Dogs."

Nowadays, that dog is a 16-month-old English Bulldog mascot named Lance Cpl. Legend.