There's no such thing as Presidents' Day.
According to United States federal government code, the holiday is named Washington's Birthday, and has been since it went nationwide in 1885.
But common practice is more inclusive. The holiday expanded to add in other U.S. presidents in the 1960s, and the moniker Presidents' Day became popular in the 1980s and stuck. It may be that George Washington (b. February 22, 1732) and Abraham Lincoln (b. February 12, 1809) still get the lion's share of attention—and appear in all the retail sale ads—on the third Monday in February, but the popular idea is that all 44 presidents get feted.
Mount Rushmore is a lot like that one day a year writ large—and in granite. It's carved 60 feet (18 meters) tall and 185 feet (56 meters) wide, from Washington's right ear to Lincoln's left.
The monument's sculptor, Gutzon Borglum, grew up in Idaho, a first-generation American born to Danish parents. He studied art in France and became good friends with Auguste Rodin. Borglum mostly worked in bronze, but in the early 1910s he was hired to carve the likenesses of Confederate leaders into Stone Mountain in Georgia.
He was about to be fired from that job for creative differences about the same time that a South Dakota historian named Doane Robinson had an idea. Robinson wanted to have a monument carved into the Black Hills of South Dakota, maybe Western historical figures like Chief Red Cloud and Lewis and Clark, each on their own granite spire. (Plan a road trip in the Black Hills.)
Robinson hired Borglum and gave him carte blanche. Borglum was looking for something with national appeal, so he chose to depict four presidents: George Washington, Thomas Jefferson, Theodore Roosevelt, and Abraham Lincoln.
Borglum wanted to represent the first 150 years of the nation's history, choosing four presidents as symbols of their respective time periods. He took a tour of western South Dakota, searching for an ideal canvas.
The sculptor was looking for three things: a surface strong enough to sculpt, a mountain big enough to hold several figures, and a mountain face that received morning sunlight. Mount Rushmore fit the bill and was already part of a national forest, so it was easy to set aside as a national memorial.
Work started in 1927. Calvin Coolidge attended the dedication ceremony. It took 14 years to finish the carving, conducted mostly in summertime because of the area's harsh winters.
There were approximately 30 workers on the mountain at any give time. In total about 400 had worked on it by the time the monument was finished. Though the project involved thousands of pounds of dynamite and perilous climbs, not a single person died during the work.
Borglum himself died of natural causes in 1941, though, just six months before the project was declared "closed as is" by Congress that Halloween. His son Lincoln—named for his father's favorite president—took over.
In the photo above, a worker refines the details of Washington's left nostril.
About 90 percent of the mountain was carved using dynamite, which could get within 3 to 5 inches (8 to 13 centimeters) of the final facial features. For those last few inches, workers used what was known as the honeycomb method: Jackhammer workers pounded a series of three-inch-deep holes followed up by chiselers who knocked off the honeycomb pieces to get the final shape. Then carvers smoothed the "skin's" surface.