I visited this WHS in August 2014. After learning that the Altamira Cave was closed to the public and that it was only possible to visit the replica museum, I decided to make a reservation online to visit the group of caves of El Castilo, Las Monedas and Las Chimeneas inscribed together with Altamira. I opted for the first visit in the morning on a weekday to avoid tour groups and indeed I was lucky. The guided visit was in Spanish but I was able to follow the gist of what the guide was saying and anyway my main purpose was to visit the actual caves and to see the original paleolithic art illuminated by the guide's torch. The main highlight of the El Castilo cave were the hand impressions while the highlight of the other caves were animal paintings of deer and bisons. Photography is not allowed but I managed to take a short video of the hand impressions as I exited the cave and a couple of photos too which I'll treasure knowing that sooner rather than later the original caves will have to be closed to the public to avoid damage caused by fungi diseases. I enjoyed my visit mostly because I managed to see the original paleolithic art this time round, however I must say that the Lascaux cave drawings are more elaborate (even though what you see is a replica).