More than a million people flock to the remote desert on the Arizona-Nevada border each year to "Ooh!" and "Ahh!" at a 75-year-old marvel of engineering, the majestic Hoover Dam.
They've all seen the pictures, but it's not the same.
One kid exclaimed, "Boy! It's HUMUNGOUS!"
At 726 feet, it would tower over the Washington Monument. The concrete is enough to pave a road from New York to San Francisco, and enough to build a sidewalk around the equator.
That's what it took to stop the mighty Colorado River dead in its tracks.
As for environmental concerns, Michael Hiltzik, author of "Colossus," a new history of the Hoover Dam, says conservation had a different meaning back then. It meant not protecting resources, but exploiting them.
After all, the region had suffered devastating floods and droughts and the West needed power and water for its developing cities. So in 1931, when Herbert Hoover was president, construction began. The question wasn't should we build the dam, but rather can we?
"It was well understood that this was going to be possibly the most challenging project that engineers ever had faced. The builders had to invent construction techniques. They had to invent equipment. This was a dam that had to be invented as it went up," Hiltzik said.
That discouraged no one. This was the Depression. Breadlines were growing. People were desperate. The dam meant a job.
Thousands came. Soon, a whole town - Boulder City - sprang up near the site.
In their eagerness, many workers discovered they'd underestimated both the risks of the work and the misery of the desert sun.
"It was like working in a blast furnace, "Hiltzik said. "In that first killing summer, you had scores and scores of men keeling over from heatstroke and dying from what the contractors called "natural causes."
In 1981, several former workers spoke with a documentary crew.
"I saw 145 degrees down there in that canyon, with no air circulation. If you had a little breeze, then you'd get maybe down to 130, or 125," a former worker said.
Officially, 96 men died building the dam. Unofficially, no one really knows.
In the deep tunnels men would sicken from breathing carbon monoxide from truck exhaust …while far above the canyon floor workmen's lives literally hung in the balance…
"They were known as the "high-scalers" and they're chiseling away. They're boring holes for dynamite. They're placing dynamite - boom! And they're doing it suspended in midair. Some of them got reputations as being real acrobats. And people would come to the top of the cliff to watch them perform," Hiltzik said.
The project was finished in 1935 for more than 100 million dollars, equivalent to about a quarter of the country's entire annual public works budget back then. Franklin Roosevelt himself showed up to dedicate it.
It's official name was Boulder Dam, Democrats in power having stripped Republican Hoover's name right off it.
"Hoover, of course is out of office. Not only was he not invited, he'd asked to be invited. It was a day full of ceremony - many, many, many speeches, including a keynote speech by the president himself, and Herbert Hoover's name wasn't even mentioned once," Hiltzik said.
It would take 14 years - and a Republican Congress - to re-name it Hoover Dam. By then it had started its long and storied movie career, from Hitchcock's "Saboteur" in 1942, to "Transformers" just a few years ago.
And in between, in 1964's "Viva Las Vegas," Ann Margaret and Elvis flew over it. In "National Lampoon's Vegas Vacation," Chevy Chase climbed up it. In "Superman," the bad guys detonated it, and the Super One re-assembled it.
And now AT&T is draping it in orange.
Ken Rice, who manages the dam, thinks he understands the appeal.
"I think success. Power. I mean you look at Hoover Dam, 75 years doing what we've been doing for 75 years, storing that water, deliver that water and creating power, you know that's a story of success," Rice said.
He appreciates its beauty as well: the clean Art Deco lines, striking sculptures, Italian tile floors, those gleaming turbines.
The dam today supplies vital power for more than a million people and water for some 20 million, but at a cost. Drought, growing populations, higher demand and other water projects have reduced the once mighty Colorado to a trickle when it reaches the sea. Wildlife habitats - perhaps whole species - have been lost.
Even the dam's most diehard fans concede it probably wouldn't be built today, but they insist it was both right - and remarkable - to build it then.
"Tthe foresight that those folks had to build this structure back in the 30's, to harness the Colorado, was just amazing at that point in time, that those folks could even think of that," Rice said.
"It's not the tallest dam, and it's not the biggest dam, but its got a grace and power that really takes people … really seizes the imagination. The simple lines that it has - you know the artistic beauty of the design is really something unique," Hiltzik said.
The dam's future seems secure. Its birthday present will be a new bridge across the canyon, a perfect vantage point from which to exclaim the obvious: Hot Dam! And Happy Birthday.
For more info:
Hoover Dam, Bureau of Reclamation, for more information on the Hoover Dam and the Colorado River
"Colossus" by Michael Hiltzik (Simon & Schuster)
Nick Molle Productions
Pete McBride Photography