The monarch’s 3,000-mile migration is one of the most epic and dangerous journeys on Earth. Each fall, butterflies born in Canada and the U.S. navigate south to the same Mexican fir groves that sheltered their grandparents and great-grandparents. But habitat loss and extreme weather are pushing this iconic traveler toward the edge—raising urgent questions about whether the migration can survive. Read more: https://on.natgeo.com/4or3H0p Explore the World with National Geographic subscriptions: