ST. SIMONS, Georgia -- At the age of 93, just making it down all four steps of an RV is quite a feat. It’s even more remarkable to wake up at 5 a.m. for a five-mile run.

And at 93, what’s most amazing of all, is that Ernie Andrus’ recent jog in St. Simons, Georgia, was just the final leg of a much, much longer run -- a run that began nearly three years and 3,000 miles ago at the Pacific Ocean.

Ernie Andrus CBS News

“I’m running the whole thing, every step of the way,” Ernie told us when we first met him just outside Phoenix as he slowly inched his way through the Sonoran Desert.

He would run five miles, get a ride or hitchhike back to his vehicle, then run the next five miles two days later.

It’s all for one purpose. “I want people to know what the war was all about and what it took to win it,” Ernie explained.

Specifically, the old Navy man was running to raise awareness for an unsung hero of World War II -- a ship he served on called an LST, or landing ship tank. It’s how the allies got heavy equipment onto beaches.

There’s one you can visit in Evansville, Indiana​, and Ernie thinks people really need to go.

“This shouldn’t be forgotten,” he said. “Eisenhower and Churchill both made a similar remark that it’s the ship that won the war. ... Without ‘em how could you ... even [take] Normandy?”

Ernie’s route across America started at the Pacific Ocean in San Diego. CBS News

Which is why, 70 years later, Ernie was out there returning the favor all by himself. But that didn’t last long.

“I joined him in Mississippi. Ran in Mississippi, Alabama, Florida, and now Georgia,” one fellow runner told us. Another said he ran 44 legs with Ernie.

He had quite a following the second time we saw him in Waco, Texas​ -- but that was nothing compared to what we found last weekend in St. Simons. Hundreds of people from across the country had joined Ernie’s army.

“The American people are the most loving and generous people in the world,” Ernie said.

Three years ago most people thought there was no way a man in his 90s could make it across the country. And for good reason -- before him the oldest person to do it was a mere 73.

Ernie Andrus finished his run in St. Simons, Georgia, with hundreds of supporters watching. CBS News

But there he was, on the soft sand of the Atlantic.

He stormed the beach one last time​, to fervent chants and flying colors, showing us all that the greatest generation is no less great today.

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