One of the many highlights of my France trip was a visit to Pech Merle Caves. These caves featured stalagmites and stalactites over 2 stories tall and true, actual cave drawings done 230,000 years ago.
Please see http://www.pechmerle.com/english/introduction.html for information and google Pech Merle for more images. Since we couldn't take photographs, we created our own 'cave paintings' when we returned to the studio. FUN!