ayauhtitlan.

in ye uecauh: inic nican cen Mexico: ic mitoaya: ca mixtitlan, ayauhtitlan oquizaco in Españoles: anozo aca cenca mauiztique, cenca mocuiltonoani = when the Spaniards came here, throughout Mexico it was said: Out of the clouds, out of the mists. It was also said about those who were highly esteemed and very rich.
Thelma D. Sullivan, "Nahuatl Proverbs, Conundrums, and Metaphors, Collected by Sahagún," Estudios de Cultura Náhuatl 4 (1963), 144–145.