October 2016
The Olmec Heads 

A long-standing enigma surrounding the Olmec civilization is the significance of the colossal stone heads found at the Olmec sites. Till date, 17 monumental stone heads have been recovered; 16 from the Olmec ceremonial centers at San Lorenzo, La Venta, and Tres Zapotes, and a solitary one - the La Cobata head - which is also the largest, from a mountain pass in Sierra de los Tuxtlas. The La Cobata head weights nearly 40 tons while the smallest one is close to 6 tons.