Introduction

Crop marks are patterns visible in a field, but their origins aren't from up above. No, these crop marks originate from below and it all has to do with archaeology. In places where there used to be a ditch that became filled in over time, hecrops planted above those spaces have more fertile soil than the areas around it. So in times of drought, the plants growing above those ancient ditches look more green and lush. Wherever there are walls, though, the soil there is more shallow than other areas. And if you add in the invention of the airplane, you have a recipe for discovery,. There are far too many examples to list here, but every time