You cannot visit the caves at Lascaux or Chevaut to see the ice age cave art but there are several other caves in France where you can still go and see the art in person. I have been fortunate enough to visit three. In 2007 I visited the cave of Niaux in the Pyrenees mountains. The Magdalenian art of horses, wisent and even a weasel date to 17,000-11,000 ybp. The second was the cave of Pech-Merle in Occitania 2012 which mostly has Gravettian art from 21,000-33,000 ybp. The horses here are spotty and there are also paintings of wooly mammoths. The third was the cave of Cougnac in 2017, also in Occitania which has art from both the Gravettian and Magdalenian periods. The most impressive art here are the depictions of an ibex, and of a large elk or Megaloceros containing a human figure’s hindquarters.
These paintings are inconceivably old and put us in touch with the origins of Europe and the first men - a life changing experience. I doubt they will remain open to the public forever...