Even without digging, geophysics enables us to see the archaeology beneath the ground surface. By mapping this buried archaeology it is often possible to interpret how old a site is and what it might have been used for. But how does geophysics work? What is it really measuring? Are there any limitations? If geophysics can do so much, do we still need to dig? This talk will outline how the different methods used by geophysicists work and what they actually reveal.