Cave paintings are not only of interrest for speleologists, but also for archaeologists and artists. In the last years many books with beautiful pictures have been published.
And this is really necessary, as most caves with paintings are closed to the public. The unique climate of the caves with the low but constant temperature and the high humidity is ideal for the paintings. The climate in public caves changes slightly, as the visitors bring in warmth and dust, light and carbon dioxide. The light allows the growth of plants, and so its just a matter of a few years until the paintings are gone forever!
The only "environment friendly" way to visit cave paintings is one of the following books: