Mike Brodie began train-hopping in 2002 at the age of 17 when he left his house unannounced with a few belongings.

"Two weeks later I was gone — this was it, I was riding my very first freight train."

From 2004 to 2009 Brodie rode more than 50,000 miles through 46 states, documenting who and what he encountered along the way with a Polaroid camera before switching to 35mm film in 2006.

The Polaroid Kid showcased his pictures in the book "A Period of Juvenile Prosperity," depicting a gritty youth subculture of freight train hoppers and squatters.

“I know almost everyone I shoot,” Brodie says, “Three of the women in the book are ex-girlfriends and a couple of the guys … are best friends.”