Reply #5: I think that there are older known structures...

[Orsino]

...though I can't vouch for the dating at this Czech site: http://www.donsmaps.com/dolnivi.html

Inside the largest hut, about 50 feet long by 20 feet wide, were five shallow hearths dug in the floor. One was equipped with two long mammoth bones stuck in the ground to support a roasting spit. In these relatively comfortable surroundings it is easy to imagine a man sitting on a boulder making tools-working with the purposeful, deceptively slow movements -of a master craftsman, using a bone hammer to strike delicate blades from a cylindrical chunk of flint, the core. Meanwhile, from a far end of the hut might have come a clear, high-pitched sound like a bird's call. Its source would have been a woman blowing into the end of a piece of hollow bone that had two or three holes pierced in its length-what humans some 25,000 years later would call a penny whistle has been found at Dolni Vestonice.