Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

People on horses riding through a forest alive with monarch butterflies. Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Ro...

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....

Every year, from January to the end of March, millions of monarch butterflies make a 4000 kilometre migration to breed in El Rosario where the world's largest colony of monarch butterflies are found....