Twenty-eight years ago today, on August 14, 1997 (July 12, 1997 in the lunar calendar), scientists discovered the earliest human footprints. On August 14, 1997, two scientists from the United States and South Africa announced in Washington that they had discovered fossils of human ancestral footprints from 117,000 years ago, the earliest human ancestral footprints ever discovered. The set of footprints was discovered in September 1995 by American paleoanthropologist Lee Berg and South African geographer David Roberts in rocks off the Atlantic coast, about 97 kilometers north of Cape Town, South Africa. After nearly two years of research, they believe that this set of footprints was left by human ancestors. The footprints were 21.6 centimeters long and may have been the footprints of a woman with a height of 1.6 meters. At that time, after a rainstorm, the beach was wet, and the footprints were soon buried by the fine sand blown by the strong wind. After a long time, they formed gravel rocks, which preserved the footprints.