The correct answer to this open question is the following.
Unfortunately, you did not include the lecture, so we do not know what was the information included in the lecture. Just you know it.
However, trying to help you, we can answer based on our knowledge of this topic.
These are the three main European caves.
1.- Altamira cave in Spain. More than 35,000 years old.
2.- Lascaux paintings in France. More than 17 years old.
3.- Magura cave in Bulgaria. More than 10 years old.
These caves are impressive historical references that have been researched by experts to understand what could have been the meaning our ancestors tried to express with their paintings. Of course, there are many interpretations and controversies around the interpretation of what is described. However, it is our responsibility to take care of these important paintings that give us an idea of what was the vision of the reality of those primitive humans.