The cave paintings (Lascueaux, Three Brothers, and others) range upwards to 20,000 years old.
Stonehenge is only about . . . six thousand years old, IIRC, and the other triliths, dolmans and stone circles not much older.
Venus figures seem to run about the oldest. I think the Venus of Willendorf is about 40,000, but it’s carved out of limestone, so maybe the datings a little hard to pin down.
Does anyone know for sure what the oldest known piece of artwork is?
Will work for sig line.
AFAIK, the oldest known piece of art is indeed the Venus of Willendorf, from c. 28000 - 25000 BC. Of course, given the 3,000 year range, there are likely some sculptures that are older but we can’t determine this accurately from our dating techniques. Carbon-14 dating of charcoal sets the Lascueaux cave paintings as being c. 13000 BC. Stonehenge was erected in 2000 BC.
Ok one reference I got says Lascueaux is 30,000 BCE but what’s 10,000 years.The Veni may be as old as 50,000. In another something I read once, I think , there are some lines incised on charred flat bones and antlers that are older. The lines seem to have been purposly carved after the charring , care seems to have been taken in spacing and length, there is even some crosshatching, but is it art? The eternal question. The proceedings of the PEA (Paleolithic Endowment for the Arts) were lost in the memory knot crash of Y-20K so we may never know. As for the Venus figures, they are definatly art,even if they seem to be prehistoric pornography,with their lush bodies. They were ,after all, granted PEAbody awards.
“Pardon me while I have a strange interlude.”-Marx
What’s your source for the Lascueaux caves being 30000 years old and the Venuses being 50000? I’m not quibbling, if my dates are generally held to be incorrect I would like to know. My info comes from my old college textbook: Art Through the Ages I: Ancient, Medieval, and Non-European Art, Ninth Edition, Harcourt Brace Jovanovich, 1991.
If you’re not limiting the artists to being humans, there were some bohemian dinosaur artists whose petrified dung sculptures are at least 65,000,000 years old. 
Desmond Morris in one of his series on TLC showed what I think he said was the oldest known piece of art.
It was a smooth flattish stone that had a “face” on one side.
It hadn’t been carved, I don’t think. I think the “face” was incidental, like the “Mars face,” however, it was found in some area with some other very primitive artifacts.
He surmised that that stone was kept because the primitives realized that one side looked sorta like a face.
Don’t remember the exact age, though.
I think Chauvet is now considered the olderst parietal painting, at maybe 32000 BC, while the Venuses show up beginning around 28000. But if you have a looser definition of art then the acheulean handaxes are far earlier (if we accept art as something which is designed for a particular pre-conceived aesthetic form independent of formal function) in the hundreds of thousands of years range. I think some decorative spear-throwers are also earlier than the venus figures or paintings. Remains of blobs of non-local ochre have been found with some very old remains, too, indicating that there was some sort of ornamentation going on much earlier than the parietal works.
“He surmised that that stone was kept because the primitives realized that one side looked sorta like a face.”
If so, then the “found art” of Duchamp is actually horribly consertavive…