1. A year or two ago we read that The National Geographic Society was donating $2M to this search. I've read that the US State Department nixed that effort due to the companys' affilation with the communist government of Cuba.
2. Dr Robert Schoch (Geogolist/Geophysist) said in his recent book, Voyages Of The Pyramid Builders, that from what he had seen up to that point, that he thought these were natural structures.
3. Plato mentioned that The Alantians had a metal (gold/copper alloy), forgot the name he used, but, a copper/gold alloy occurs naturally in the area of Teotihuacan and no where else in the world.