The size of Mount Rushmore faces is 60 ft, from the forehead to the chin. Each face is as high as a six-story building. Each eye is 11 feet wide. The elevation is 5,725 feet. The total area it occupies is 1,278.45 acres (5.17 km2).
The four US Presidents are Abraham Lincoln, George Washington, Teddy Roosevelt and Thomas Jefferson. The mountain sculpture can be found at Keystone, Black Hills in South Dakota. The mountain is at the northeast of the Harney Peak Granite Batholith.
The four were selected to symbolize the growth, founding and preservation of America. The project was supervised by John Gutzon Borglum.
Building commenced on August 10, 1927. Due to the size of Mount Rushmore, 400 sculptors had to assist Borgulum. During dedication day, President Coolidge was in attendance. The costs were shouldered by the government and some members of the private sector. The first stage involved dynamiting rocks.
The workers used hammers, drills and other tools. It took 14 years to finish the project. Borgulum passed away before the work could be completed. His son Lincoln took over supervision duties. In 1941, the sculpture was finished.
The rocks are made up of fine-grained granite outcroppings. This is a type of cooled down volcanic rock. Mica schist, a crystalline rock, was also used. The whole area itself is made up mostly of granite.
The batholith magma came into the mica schist rocks 1.6 billion years ago. During the late Precambrian Period, the Black Hills granites were eroded. During the Cambrian Period, sediments and sandstones buried it. By the Paleozoic Era, the area got buried but emerged 70 million years ago.
Fauna and Flora
Some of the birds in the area are meadowlarks, hawks, bald eagles, vultures and turkeys. On certain occasions, the birds make nests on the mountain ledge. Other birds in the area are woodpeckers, nuthatches and songbirds.
Land based mammals include the bobcat, bighorn sheep, coyote, badger, beaver and the raccoon. Porcupines, squirrels, skunks, chipmunks and mice proliferate as well. There are many kinds of reptiles in the area.
The Starling Basin and Grizzly Bear brooks have plenty of fish. Some mountain goats can be seen as well. Coniferous trees are found at the lower elevations. Other plants include cottonwood, Black Hills spruce and bur oak.
The size of Mount Rushmore and its sculptures have become a cultural landmark. It can be seen in movies, TV, and other media.