At present, I'm designing a unit on prehistoric cave art for the upcoming school year, and like so many of the Social Studies topics I come across, there's a clear need for some armchair travel in order to fully appreciate its awesome-ness.
The most famous examples of Paleolithic cave art are found at
Altamira, in Cantabria, Spain, and
Lascaux, France, and several other notable European cave sites are concentrated in these two countries. Both of the aforementioned caves were discovered by intrepid children, and are now highly protected UNESCO World Heritage sites. After some 15,000+ years of isolation, the carbon dioxide exhaled by tourists during the first years of public display began to damage the paintings, so both Altamira and Lascaux are pretty much impossible to experience first-hand these days. Altamira has close to a three year waiting list, and Lascaux is open to a handful of scientists for a few days out of every month. You can visit accurately represented replicas that have since been created for preservation's sake, but not the real thing.

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Above: Altamira)

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Above: Lascaux)
Outside of Europe, as expected, the materials and themes displayed in prehistoric cave art vary quite a bit. For example, the paintings at
uKhahlamba/Drakensberg, South Africa, depict uniquely African predators chasing spear-toting humans across the rock walls. Compare that to the figures represented in Australia's
Kakadu National Park (which portray pre-Aboriginal weaponry and the pursuit of kangaroos) or India's
Bhimbetka rock shelters (where everyday life is drawn in colors that are still vivid some 9,000 years later), just to name a few. These non-European cave art sites are often considerably more accessible, sometimes because the site itself is more exposed and therefore less susceptible to carbon dioxide accumulation.

(
Above: uKhahlamba/Drakenberg)

(
Above: Kakadu National Park)

(
Above: Bhimbetka)
Anyway you look at it, the various symbols on these caves' walls, though relative simplistic, are remarkably powerful. Just imagine being the nine-year-old girl who strolled into Altamira for the first time in modern history and took it all in amidst the deafening silence. Or maybe the group of teenagers taking their dog for a walk, who stumbled upon "the Sistine Chapel of pre-history" (as Lascaux is popularly known) and had it all to themselves for a few hours. If that doesn't make you want to be an explorer, nothing will.