Monarch butterflies travel thousands of miles to Mexico. An inside look into the mystery migration. [Video]

After flying some 3,000 miles from the northern U.S. and Canada to a remote forest in Central Mexico for the winter, tens of millions of monarch butterflies are making their way back north. 

These are no ordinary monarchs. While most monarchs live about a month, these monarchs, a “super generation,” can live up to nine times longer. It’s believed monarch super generations have been making this epic migratory journey for thousands of years, but it’s still something of a mystery how this super generation knows where to go. 

“That’s one of the most magical things that could happen in the natural world,” said Jorge Rickards, director of the nonprofit World Wildlife Fund in Mexico.

Monarchs in Mexico

Starting in late October, monarchs come to remote mountains in Michoacan, central Mexico. They roost in patches of fir and pine trees up to 11,000 feet up. This year, some 66 million monarchs spent their winter in the Mexican forest, but it can be …