Mount Rushmore was built over a period of 14 years, starting on October 4, 1927, and finishing on October 31, 1941. The project involved sculptor Gutzon Borglum and about 400 workers. Borglum passed away in 1941 before the work was fully completed, but it was declared finished later that year. The monument features the faces of four U.S. Presidents—George Washington, Thomas Jefferson, Theodore Roosevelt, and Abraham Lincoln—and was carved to symbolize the founding, expansion, preservation, and unification of the United States.