Some of the challenges they face in their journey include exorbitant fees charged by human smugglers, dehydration and injuries while navigating tough terrain.
While those coming from Mexico have shorter trips, for many migrants from Central America, this journey traveling north can mean riding on top of a freight train dubbed "La Bestia," or "The Beast." Migrants adopted this moniker for the train as many riders have been maimed, hurt or killed as they get on and off.
AFP journalists spent 24 hours with migrants crossing Mexico in search of the "American Dream."
These are their photos:
AFP contributed to this report.