At one time the Shinetsu Honsen (or Shinetsu Main Line) was one continuous line. Currently, this JR East operated line is divided into three geographically distince sections as follows:
How it got to that situation is another story, but the name of the line comes from the old names for Nagano Prefecture (Shinano 信濃) and Niigata Prefecture (Echigo 越後)
Shinetsu Honsen Station names and distances from Takasaki Station in Nagano Prefecture to Niigata Station in Niigata Prefecture(in different sections)