Apart from Atlantis and Lemuria, Edgar Cayce mentions a third highly advanced civilisation with technological accomplishments that equal or surpass ours. He usually refers to it as OG, though sometimes Ogum, Om and Oz are found, too, in the life readings.
The Ogs would have lived in what is present-day Peru (and Bolivia), which means they could have been the ones that built Tiahuanaco.
There may be connections with the Og-Min, and with the ancient Kingdom of An, which was also said to have been in the Andes.