Watch: Tracking the monarchs to Mexico

Monarchs spend the winter in the mountains of Michoacan, Mexico. ©Pablo Leautaud

Before the 1970s, where monarch butterflies overwintered was a mystery. Then researchers succeeded worked with Mexicans to trace the migration to the hills of Michoacan. In the video below, Atlas Obscura details the story of the discovery and the importance of the monarchs to the region.