In the old days, a prime spot for a hobo camp was any place where a train would have to stop or slow down such as a passing siding or signal, or a steep grade. Also leaving a freight yard as a train was just starting to pick up speed. People sometimes romanticise hobos but there have always been some who were hardened criminals or druggies. Some years ago I saw a program on cable TV about certain individuals, mostly out West, who styled themselves "Freight Train Riders of America". It sounds innocent enough, but they were really the worst sort of criminals. Supposedly to be accepted among them, one first had to kill someone else. One man in particular was a serial killer who, after commiting a murder, would calmly sit and read from his Bible. There were interviews with some railfans-turned-amateur-hobos who had had very scary experiences on the rails. That show should be required viewing for anyone thinking about hanging around freight yards.