 The Coatlicue statue was excavated in the main plaza of Mexico City in front of the National Palace on 13 August 1790 during the excavation of a water canal.A few months later, on 17 December 1790, the sun stone (also known as the "calendar stone") was found about 100 feet away.The momentous discovery of these two statues, along with the 1791 excavation of the Tizoc Stone, initiated a new phase of research on the Templo Mayor as contemporary scholars attempted to interpret their dense symbolism and decipher their meanings.