There is a little bit of grass (in summer) and a few trees, but the majority of the exhibit is concrete. It is a very old enclosure inhabited by several very old bears. Last I heard there were three bears remaining there, though that number could have dropped. At one point not too long ago there were six.
During my visit, I just saw one bear left. It didn't seem bothered by the concrete, and most of the time was chilling in a waterfall feature just outside of the picture.