''Makes you think though doesn't it DB
Much like the Carnac stones and the Nazca lines''
Not enough information to determine what the truth is. Could be that some are are a hoax, others may be parts of shells or other fossils. Who knows.
It seems unlikely that a space faring civilization used nuts and bolts and microchips as we currently do. Nor is there evidence for a large scale industrial earthly civilization 300 million years ago.
