Mount Rushmore National Memorial is centered on a sculpture carved into the granite face of Mount Rushmore in the Black Hills in Keystone, South Dakota. Sculptor Gutzon Borglum created the sculpture's design and oversaw the project's execution from 1927 to 1941 with the help of his son Lincoln Borglum. The sculpture features the 60-foot (18 m) heads of Presidents George Washington (1732–1799), Thomas Jefferson (1743–1826), Theodore Roosevelt (1858–1919), and Abraham Lincoln (1809–1865), as recommended by Borglum. The four presidents were chosen to represent the nation's birth, growth, development, and preservation, respectively. The memorial park covers 1,278.45 acres (2.00 sq mi; 5.17 km) and is 5,725 feet (1,745 m) above sea level.
Between October 4, 1927, and October 31, 1941, Gutzon Borglum and 400 workers sculpted the colossal 60-foot-high (18 m) carvings of United States Presidents George Washington, Thomas Jefferson, Theodore Roosevelt, and Abraham Lincoln to represent the first 130 years of American history. These presidents were selected by Borglum because of their role in preserving the Republic and expanding its territory. The carving of Mount Rushmore involved the use of dynamite, followed by the process of "honeycombing", a process where workers drill holes close together, allowing small pieces to be removed by hand. In total, about 450,000 short tons (400,000 long tons) of rock were blasted off the mountainside. The image of Thomas Jefferson was originally intended to appear in the area at Washington's right, but after the work there was begun, the rock was found to be unsuitable, so the work on the Jefferson figure was dynamited, and a new figure was sculpted to Washington's left.
