Right in the center of the island nation of Madagascar there’s a strange, almost perfectly circular geological structure. It covers a bigger area than the city of Paris — and at first glance, it looks completely empty. But right in the center of that structure, there’s a single, isolated village: a few dozen houses, some fields of crops, and dirt roads stretching out in every direction.

When we first saw this village on Google Earth, its extreme remoteness fascinated us. Was the village full of people? How did they wind up there?