In the northeast corner of Arizona (USA) is an area known as the Arizona Petrified Forest National Park. The forest in question is actually over 200 million years old and various interpretations have been placed on the fossilised logs by the native North Americans. These range from them being the bones of a great monster which was slain by their ancestors, to the arrow shafts of their thunder god.
     There are now several museums located about the park, which explain the history with a greater degree of accuracy. One anomaly, however, caught the eye of a group of researchers. They noticed an area which has sandstone slabs sticking out of the ground. This was not a natural phenomenon and so must be man-made. There then ensued a labour intensive investigation by a team of 10 archaeologists who walked over the area in a methodical grid pattern, observing and recording everything they found, from pieces of stone tools to fragments of pottery.
     All these finds were recorded using GPS coordinates and eventually an amazing discovery was unfolded. What emerged was a picture of a village settlement estimated to be 1,300 to 1,800 years old, comprising a series of pit houses, half buried, with sandstone walls and what would have been roofs made of organic material. It was estimated that there were between 50-70 houses, which equated to a population of 100-150.
     Park superintendent Brad Travers is quoted as saying "It's the time when civilisation in our area was starting to gather in villages - not individual hunters and gatherers anymore". He went on to say "This is an important discovery not only because of what we found, but the fact that it's in a national park now means it'll be something that'll be protected for a long time".

Edited from AZ Central, International Business Times (10 October 2014)