Hi, Q!
I suppose an archeologist can claim anything they like, but usually when one makes claims that don't fit in the "established" order of things, other archeologists are likely to present some serious challenges and non-supportive critiques. For instance, it is well established that stone tools have been around longer than 11000 years...a lot longer. And this is supported and reinforced across many multiple examples examined by many and varied archeologists and anthropologists. On the other hand, I guess it would depend which burial mounds one is referencing...I believe the ones in Ohio and Indiana for example are dated at least 5 thousand years ago and probably more, but the Mound Builder culture is still a bit of a mystery, and seems (much like the Anasazi) to have ended rather abruptly. By contrast, the burial mounds in Ireland are comparatively more recent.
"(H)undreds of thousands of years old" implies to me at least 2 hundred thousand years, and the established train of thought at this time in archeology as I understand it, modern humans (including H. Neandertalensis, H. Erectus and H. Heidelbergensis) were using fire and exceedingly primitive tools (unworked bone, stone and sticks) right at 200 thousand years ago.
Human evolution - A look at human origins through species profiles and hominid imagery
Atlantis is a mystery that makes for a good bedtime story. I admit to some intriguing possibilities and I have long wanted to see evidence of Atlantis...but so far there is nothing in the archeological record to support it (other than some tantalizing linguistic cues from Central America). If there were some highly advanced civilization long before our own, there would be some kind of evidence laying about. We haven't found their trash dumps yet, and I hope we never find their nuclear waste "facilities."
The oldest indoor plumbing I have read about is the 10 thousand year old restroom facilities in the Orkney Islands.
This looks like an interesting anthropological resource:
Human Evolution Archaeology human origins hominid species images
Hmm, perhaps not Juan. I was watching TLC/History Channel and their program about life after man. They pointed out the fact that the farther a society evolves and becomes technically advanced, the more refined and economically minded their structures become, which means the easier it is to reclaim man's work back to the basic elements, if man is not there to maintain said structures.
Case in point: The Romans used concrete that was without reinforcement (rebarb as you know), but was denser than the concrete used today. Iron rebarb will not rust as long as the alkaline in the concrete protects it, but after 50 years concrete today, loses its alkaline, and the rebarb begins to rust, which destroys the cohesiveness of the surrounding concrete...down comes our sky scrapers and bridges and such.
The Eiffel Tower (made of wrough iron) must be painted every seven years, to protect it's integrity. Without that upkeep, the iron in the tower would dissolve within 150 years, resulting in total collapse.
Ashphalt roads without a concrete base, would dissolve within 200 years.
Sky scrapers may look like they are made of glass (which can last for ever), but their skeletons are made of steel...200 years.
CDs are good for 100 years.
magnetic tape is good for 10 years.
Library books-100 years in a dry environment (acid in the paper)
plastic-1000 years, but not in any condition that one would recognize.
brick (reclaimed brick), about 500 years.
Cars, 50 years, their steel frames 150 years.
The only reason we have a history and knowledge of folks like the Mayans and Egyptians, is because they carved it in stone...
In fact, the only thing that an observer from 10,000 years from now would see and wonder about in the US would be in the Black hills of South Dakota...and they would have no idea who's faces they were looking at, nor would they be able to discern the details of the faces there.