Narai station is located in Shiojiri city of Nagano prefecture. Trains of JR Chuo main line is running this station and it is the closest station for former Naraijuku post town of former Nakasendo highway, which is just a few minutes away.
However, limited express Shinano which run between Nagoya and Nagano stations do not call at this station. Therefore if you want to visit Naraijuku, you have to get off at Shiojiri or Kiso-Fukushima and change to local trains.
Not like other famous post towns of Nakasendo; Magome and Tsumago, Naraijuku has the closest access from the nearest station. Magome and Tsumago are unfortunately not close to the stations and you have to take buses to reach these former post towns .