Let's take a pole..... In a case of who's railroad is it, UP 5284 leads a NS unit through Mt. Pleasant, WI on CP's C&M Subdivision on 5/9/22. Pole lines have become increasingly rare these days, but the ex-MILW line between Chicago and Milwaukee still has a fair number of them left in place.
Photos showing the railroad pole lines. The pole line used four basic electrical circuits - telegraph, telephone, signaling, and power. Modern technologies of fiber optics, microwave, radio, satellite, and computers have been replacing the pole lines.