from that link — “weighs an estimated 440 tons (equal to nearly 600 full-size cars)” — a full-size car nowadays runs a bit more than a ton, so that’s wrong. But regardless, there’s no scientific dating for that site showing it to be tens of thousands of years old, as some had claimed at one time. There’s no writing there (as that page notes), but someone decided that there must be solar alignments, found out that they didn’t work, then decided that the solar alignments must have worked at one time, and figured out how long ago that would have been. That isn’t a scientific approach.