Shonan-Shijuku line is not the name of line, but it is the name of Rapid train’s route. This line connects west side of downtown Tokyo, Shinjuku, Ikebukuro and Shibuya with major cities in Saitama, Gunma, Tochigi, Kanagawa prefectures. This is a sort of commute train. But all trains have two double decker Green cars in the formation. This train is fully covered by Japan Rail Pass. Of course if you use Japan Rail Pass Green, you can take Green cars with no extra cost.
Please refer the post of Rapid service network in Greater Tokyo. You can see some images of Green car and intrerior.
Route, schedule and required time
There are two routes. (Only major stations are shown)
Utsunomiya (=宇都宮)-Omiya (=大宮)-Ikebukuro (=池袋)-Shinjuku (=新宿)-Shibuya (=渋谷)-Yokohama (=横浜)-Ofuna (=大船)-Kamakura (=鎌倉)-Zushi (=逗子)
[Maebashi (=前橋)-Takasaki (=高崎)]-Kagohara (=籠原)-Kumagaya (=熊谷)-Omiya (=大宮)-Ikebukuro (=池袋)-Shinjuku (=新宿)-Shibuya (=渋谷)-Yokohama (=横浜)-Ofuna (=大船)-Hiratsuka (=平塚)-[Kozu (=国府津)-Odawara (=小田原)-Atami (=熱海)]
The trains are operated every 30 minutes in daytime and weekend, and every 20 minutes in peak hours on weekdays on each route. So if you transfer between Omiya and Ofuna, you can take either route. You have trains every 15 minutes in daytime.
The trains stop at these following stations:
Utsunomiya-(*Most of trains stop at all stations in this section)-Omiya-Akabane-Ikebukuro-Shinjuku-Shibuya-Ebisu (Some trains skip this station)-Osaki-Nishioi (Some trains skip this station)-Musashikosugi-Shinkawasaki (Some trains skip this station)-Yokohama-Hodogaya (Some trains skip this station)-Higashitotsuka (Some trains skip this station)-Totsuka-Ofuna-Kitakamakura-Kamakura-Zushi
Most of trains stop at all stations between Omiya and Utsunomiya. But some trains stop at Hasuda, Kuki, Furukawa, Oyama, Koganei, Jichiidai, Ishibashi, Suzumenomiya only. Time required in major sections are as follows:
Utsunomiya is the gate city to go to Nikko. Usually everybody choose Tohoku Shinkansen to get Utsunomiya. Of course Shinkansen is faster than regular trains. But if you stay in Shinjuku area, you need to take local train to Tokyo station, then transfer to Shinkansen there. Lets’ see the time required.
Shonan-Shinjuku line : 1 hour 41 minutes (in case of using rapid train in daytime)
Local train+Tohoku Shinkansen : 14 minutes (Shinjuku-Tokyo by Chuo line) + 15 minutes (transfer) + 50 minutes (Tokyo-Utsunomiya by Yamabiko on Tohoku Shinkansen) = 1 hour 19 minutes
Shinkansen is faster. But it is not super different in my opinion. Especially Tohoku Shinkansen is quite slow between Tokyo and Omiya, because trains go through the residential area. Noise have to be reduced as much as possible. I do not strongly recommend you to take this train to Utsunomiya. But if you use Japan Rail Pass Green, you can take a seat in double decker Green car. It may be considerable to take this train.
If you go to Yokohama or Kamakura, please don’t think about using Shikansen. It takes 19 minutes to Shin-Yokohama from Tokyo. And also you are in same situation as going to Utsunomiya. You need to transfer to Tokyo station from Shinjuku. And also Shin-Yokohama is a few stations away from Yokohama. Shonan-Shinjuku line is much faster than Shinkansen. In case of going to Kamakura, it is same. Shinkansen do not have any stations in Kamakura. You need to transfer the train at Shin-Yokohama. Shonan-
shijuku line is quite faster.
Some of the trains are extended to operate to Maebashi, Takasaki, Kozu, Odawara. And a few trips are extended to operate to Atami on weekend only. But most of trains are operated between Kagohara and Hiratsuka. The trains stop at these following stations:
Maebashi-(*Most of trains stop at all stations in this section)-Omiya-Akabane-Ikebukuro-Shinjuku-Shibuya-Ebisu-Osaki-Nishioi-Musashikosugi-Shinkawasaki-Yokohama-Hodogaya-Higashitotsuka-Totsuka-Ofuna-Fujisawa-Tujido (Some trains skip this station)-Chigasaki-Hiratsuka-Oiso (Some trains skip this station)-Ninomiya (Some trains skip this station)-Kozu-Kamonomiya (Some trains skip this station)-Odawara-Manazuru-Yugawara-Atami
Most of trains stop at all stations between Omiya and Maebashi. Time required in major sections are as follows:
Maebashi-(15min)-Takasaki-(40min)-Kagohara-(5min)-Kumagaya-(40min)-Omiya-(same as above Utsunomiya-Zushi route)-Ofuna-(20min)-Hiratsuka-(13min)-Kozu-(6min)-Odawara-(23min)-Atami
If you go to Odawara from Shinjuku, this train is almost as fast as Shinkansen. It take 41 minutes by Kodama on Tokaido Shinkansen from Tokyo. It takes 1 hour 15 minutes by the fastest train on this line. But you need to spend another 30 minutes to get Tokyo from Shinjuku and transfer time at Tokyo station.