McCandless then travels on the Colorado River and, though told by park rangers that he may not kayak down the river without a license, ignores their warnings and paddles downriver until he eventually arrives in Mexico. There, his kayak is lost in a dust storm, and he crosses back into the United States on foot. Unable to hitch a ride, he travels on freight trains to Los Angeles. Not long after arriving, however, he starts feeling "corrupted" by modern civilization and decides to leave. Later, he is forced to resume hitchhiking, after being beaten by railroad police.