Mapping the Tokaido Main Line Branches and Freight Lines ― Riding the Tokaido Freight Line on Limited Express Shonan

The Tokyo–Odawara section of the Tokaido Main Line (104.6 km) is a complex stretch where branch lines and freight lines are tangled together. The passenger lines alone include the Tokaido Line, Keihin-Tohoku Line, and Yokosuka Line running in parallel, with several freight-only lines branching off on top of that. Tracks you never ride on are running right next to the ones you use every day.

This article lays out the full picture, then documents riding the freight line sections accessible by scheduled train—specifically the Limited Express Shonan.

Branch and Freight Line Overview

The Tokaido Main Line has the following branch and freight lines in the Tokyo–Odawara section alone.

The Hinkaku Line can be ridden on scheduled Yokosuka Line trains. The Tsurumi–Hazawa-Yokohama-Kokudai section of the Hazawa Line is covered by the Sotetsu–JR direct service. The remaining Hazawa-Yokohama-Kokudai–Higashi-Totsuka section and the Higashi-Totsuka–Odawara parallel freight line are only accessible on certain trains like the Limited Express Shonan.

The Tokyo Freight Terminal Branch, Tsurushio Line, and Takashima Line have no scheduled passenger service and can only be ridden on chartered group trains.

Service Patterns and Routes

With so many branch lines, trains heading “toward the Tokaido” take different tracks depending on the service.

Tokaido Line: Tokyo–Odawara. Runs on the Tokaido Main Line passenger tracks throughout.

Keihin-Tohoku Line: Runs parallel to the Tokaido Line from Tokyo to Yokohama, then continues as the Negishi Line through to Ōfuna. South of Yokohama, it takes a different route from the Tokaido Line.

Yokosuka Line: Tokyo to Shinagawa runs underground on the Sobu Rapid Line route. From Shinagawa, it enters the Hinkaku Line, passing through Nishi-Ōi, Musashi-Kosugi, and Shin-Kawasaki to reach Tsurumi—bypassing Yokohama and Kawasaki via an inland detour. There is no Yokosuka Line platform at Tsurumi; trains pass through and merge onto the Tokaido Line. Continues via Yokohama to Ōfuna, then enters the Yokosuka Line proper toward Kurihama.

Shonan-Shinjuku Line: From Shinjuku via the Yamanote Freight Line and Ōsaki Branch onto the Hinkaku Line, following the same route as the Yokosuka Line to Tsurumi. Merges onto the Tokaido Line and continues via Yokohama to Ōfuna. At Ōfuna, splits into Tokaido-bound services (toward Odawara) and Yokosuka-bound services (toward Zushi).

Sotetsu–JR Direct Service: From Shinjuku direction via the Hinkaku Line to Musashi-Kosugi → Tsurumi. At Tsurumi, enters the Hazawa Line and continues via Hazawa-Yokohama-Kokudai onto the Sotetsu Line.

The Hinkaku Line and Hazawa Line are shared by multiple service patterns. Tsurumi is the junction where the main line and branch lines converge and diverge, though it has no platforms for the Yokosuka Line or Shonan-Shinjuku Line—no boarding or alighting is possible.

Riding the Freight Line on Limited Express Shonan

The Limited Express Shonan is the way to ride both the Tokaido Freight Line parallel section (Higashi-Totsuka–Odawara) and the Hazawa Line on a scheduled train. Shonan is a weekday-only commuter limited express, with morning up-trains (Odawara → Tokyo/Shinagawa) and evening down-trains (Tokyo/Shinagawa → Odawara).

Not all Shonan services use the freight line, however. The point where trains switch to the freight tracks varies by train number, and some trains run entirely on the passenger line. You can identify freight-line services from the timetable: trains that skip or don’t route through Yokohama or Totsuka are likely running via the freight line.

A freight-line service runs from Odawara on the parallel freight tracks, enters the Hazawa Line near Higashi-Totsuka, passes through Yokohama-Hazawa, emerges at Tsurumi, and switches onto the Hinkaku Line at Shin-Tsurumi Signal Station to reach Shinagawa. En route, it stops at Fujisawa and Chigasaki, which have platforms on the freight line. It does not stop at Yokohama or Totsuka, as it doesn’t pass through those stations.

Ride Report

Boarded Limited Express Shonan 6 (3076M) at Odawara. E257 series.

Leaving Odawara, the train ran on the freight tracks alongside the Tokaido passenger line. After stopping at the freight-line platforms at Fujisawa and Chigasaki, it diverged from the passenger line near Higashi-Totsuka and entered the Hazawa Line tunnel. This section cuts under the hills bypassing central Yokohama—the windows went dark. Passed through Yokohama-Hazawa, emerged above ground at Tsurumi, then switched onto the Hinkaku Line at Shin-Tsurumi Signal Station. Arrived at Shinagawa platform 8.

A regular Odawara → Shinagawa ticket works. You just need to buy a limited express ticket separately. Weekday only—no service on weekends.

Note that the Tsurumi–Hazawa-Yokohama-Kokudai section of the Hazawa Line can also be ridden on the Sotetsu–JR direct service, but the Hazawa-Yokohama-Kokudai–Higashi-Totsuka section requires the Limited Express Shonan or similar.

Unridden Freight Lines

Three lines remain unridden: the Tokyo Freight Terminal Branch (Hamamatsuchō–Hama-Kawasaki, 19.5 km), Tsurushio Line (Tsurumi–Hatchōnawate, 2.3 km), and Takashima Line (Tsurumi–Sakuragichō, 8.5 km). None has scheduled passenger service—chartered group trains are the only option. I’d like to ride them if the opportunity comes up.