In the Critias, Plato describes in detail the divine foundation of the Atlantean Empire, originally known as Poseidonis. The goldenage preserved in myth and legend, when gods walked with men, depicts the zenith of the Atlantean civilization.
The demigods of the ancient world were the Atlanteans, to whom every civilized nation owes an incalculable debt of gratitude. In the British Museum there is a remarkable document – known as the Troano manuscript – which was written over 3,500 years ago by the Mayas of Yucatan, containing an authentic account of the cataclysm which sank the continent of Atlantis.
This priceless document contains the following statement according to the translation by Le Plongeon: “In the year 6 Kan, on the 11th Mulac in the month Zac, there occurred terrible earthquakes, which continued without interruption until the 13th Chuen. The country of the hills of Mud, the land of Mu, was sacrificed; being twice upheaved it suddenly disappeared during one night, the basin being continually shaken by volcanic forces. Being confined, these caused the land to sink and to rise several times and in various places. At last the surface gave away and ten countries were torn asunder and scattered; unable to stand the force of the convulsions, they sank with their 64,000,000 inhabitants.”
Before the Atlantean continent was submerged, the initiates of the Atlantean Mysteries, carrying with them the secret doctrines entrusted to their keeping, immigrated into Egypt and other parts of the Earth where they would be safe from the impending catastrophe. Thus their secret teaching – with its priceless value to subsequent ages – was preserved. They established centers of learning and promulgated the code, clothed in language of symbolism, to such as they deemed worthy to receive it.
(from The Secret Teachings of All Ages by Manly P Hall)