El Castillo Cave
Remember how fun it was to finger-paint when you were a kid? Yeah, peeps hanging out 40,000 years ago enjoyed it too, and the Cave of El Castillo in Cantabria, Spain, is proof. Human handprints are all over the place in the cave, while the nearby Cave of Altamira houses this incredible portrait of a bison. How simultaneously chilling and exciting to think of our ancestors hanging out in these caves, making art, eating food, and discussing Geico's great insurance rates.