MEXICO CITY (AP) -- The ruins aren't particularly impressive, just some stone and clay footings for houses that probably supported walls of wood or clay wattle. And it's that very ordinariness that has experts excited.

The remnants being uncovered in the hills east of Mexico City at a spot known as Amecameca are from an ancient neighborhood - a home to regular folks.

"What makes this important is that it is a residential area, not a ceremonial or religious site," said Felipe Echenique, a historian for the National Institute of Anthropology and History, or INAH, which is in charge of reviewing the site....