Olmec Head In 1978, the National Museum of Natural History hosted "Treasures of Mexico: From the Mexican National Museum" that featured this large stone Olmec head. The Olmecs lived in south-central Mexico from approximately 1400 BC to 400 BC and are considered Mexico's earliest prominent civilization. The head weighed 5 tons and required a special steel-frame platform to display it safely inside the museum. In this photograph, riggers are unloading the head at the Mall entrance of the Museum. <a href="/items/browse?advanced%5B0%5D%5Belement_id%5D=39&advanced%5B0%5D%5Btype%5D=is+exactly&advanced%5B0%5D%5Bterms%5D=Olmec+Civilization">Olmec Civilization</a> Smithsonian Institution Archives. <a href="http://siris-sihistory.si.edu/ipac20/ipac.jsp?&amp;profile=all&amp;source=~!sichronology&amp;uri=full=3100001~!8749~!0#focus">View original</a>. 1978 (delivered to Smithsonian) No restrictions. <a href="/items/browse?advanced%5B0%5D%5Belement_id%5D=38&advanced%5B0%5D%5Btype%5D=is+exactly&advanced%5B0%5D%5Bterms%5D=1950-1979">1950-1979</a>