43°52′58.41″N 103°27′20.13″W / 43.8828917°N 103.4555917°W
The construction of Mount Rushmore National Memorial began on October 4, 1927, and took 14 years to complete. The sculptor of the memorial was Gutzon Borglum, the son of Danish immigrants. He chose the two most famous presidents, George Washington and Abraham Lincoln, and chose Thomas Jefferson because of the 1803 Louisiana Purchase (which included the land that became South Dakota). Theodore Roosevelt was suggested by Calvin Coolidge. Borglum's original design was intended to go down to their waists, but time constraints and funding only provided for their heads.
Borglum also envisaged other grand extensions to his plan, but a combination of hard granite, looming war in Europe, and lack of funding conspired against him. His team had reached 70 feet into the granite by March 1941, when Borglum unexpectedly died. The monument was deemed complete and all work shut down on October 31 of the same year.
In 1998, a titanium vault was installed in the granite floor of the unfinished hall, and filled with 16 porcelain enamel panels that include the United States Constitution and other important historical documents. A walking trail and boardwalk travels through the forests to the sculptor's studio, now a museum with information about the construction of the monument.