Who knew that prehistoric people in Europe included sound in ancient stone structures? The new field of acoustic archaeology has discovered this resonance in Paleolithic caves and Neolithic monuments. Resonance is where sounds linger or reverberate or echo the most. In painted caves in France and Spain, more of the carved and painted animal images cluster around the most resonant places. In Neolithic mounds, a long passage and cruciform chamber were used to amplify sounds. Even in open stone circles, acoustic archaeologists are pursuing a sense of how the past sounded, particularly since rituals probably included sound. This is all very new.