Migrants from around the globe are forging a grueling path to the U.S. — through the heart of the rainforest

The day began with a crack of lightning over Turbo, a Colombian port city built along a murky, trash-strewn bay ...

The flow of migrants arriving in Colombia without visas has increased dramatically over the last three years. Some 9,500 of them transited the country in the first half of 2016, more than double last year’s levels and four times the number detained in 2014.

They are part of an unprecedented wave of global migration that has seen millions of refugees descend on Europe, fleeing poverty, persecution and war. Now, with migrant ships sinking in the Mediterranean and violent attacks in Europe, a rapidly growing number of migrants from Haiti, Cuba, Asia, Africa and the Middle East are making journeys of unimaginable difficulty up through South and Central America — dreaming of setting foot one day in the United States ...