Mount Rushmore is one of America's most popular tourist attractions, visited by three million people every year to see the magnificent sculptures of the four American presidents carved into the rock. The man responsible for the Mount Rushmore carvings was Gutzon Borglum, who, along with a team of 400 men, spent 14 years working on the sculpture, before it was completed in 1941.

Given the sheer size and scope of the project, it's no surprise that Mount Rushmore was a gargantuan undertaking in every conceivable way. Originally envisioned as a monument that would help spur tourism to South Dakota, it took hundreds of workers nearly 15 years to laboriously dynamite and carve the likenesses of the four presidents' faces into the side of Mount Rushmore about 60 feet up.

As if the final product wasn't ambitious enough, the supervisors originally envisioned carving all the way down to each president's waist, and including a commemoration of achievements like the Declaration of Independence alongside the figures. Amazingly, the entire project cost less than $1 million and there were no fatalities.

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