Pole lines were pretty much everywhere along the ROW at one time but are becoming increasingly scarce. The ex-MILW (now CPKC) C&M Sub between Chicago and Milwaukee is one exception. Here Amtrak #334 cruises past the pole line in Franksville, WI on 10/21/24.
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.