It took 14 years to carve Mount Rushmore, according to KNBN. The project, depicting presidents George Washington, Thomas Jefferson, Abraham Lincoln and Theodore Roosevelt, was completed in 1941.
Clifford was born in Pierre on July 5, 1921, the Journal reported.
“I feel like Mount Rushmore was the greatest thing with which I was ever involved,” Clifford told the newspaper in 2016. “It tells a story that will never go away — the story of how America was made and the men who helped make it what it is today.