Yamitetsu Part 4: Telecom Center

Yurikamome's 7500 series EMU approaching Telecom Center Station on the Yurikamome Line

Do you remember the Japanese slang word “yamitetsu”? This term is used mainly among railfans in Japan. Today, I’d like to share a small update on my recent yamitetsu activities.

To review briefly, yamitetsu refers to railfans who enjoy taking photos of trains in the dark. The word combines “yami” (darkness) and “tetsu” (iron). In Japanese, tetsudō means “railway” — literally “iron road.” I’m still a beginner yamitetsu, but I’m slowly learning.

Recently, I visited Telecom Center to enjoy the night scenery. The building has offices, restaurants, and telecommunication facilities, and there’s an observation deck on the 21st floor with a great view of Tokyo’s waterfront area.

I originally went there just to enjoy the night view. However, about a minute after arriving, a train suddenly caught my eye — the 7500 series EMU on the Yurikamome Line! (See the photo above.)

As you may know, the Yurikamome Line is an automated guideway transit (AGT) system in the Tokyo Bay area. It opened in 1995 and connects Shimbashi and Toyosu, covering 14.7 km. The trains run on rubber tires instead of steel wheels. All trains are fully driverless and conductorless (GoA4), so the doors and operation are completely automated.

The 7500 series EMU entered service in 2018 to replace the older 7200 series. Eight sets (48 cars) were introduced. It looks beautiful at night, but if you’d like to see its daytime appearance, please check my post from 2019.

In the end, I couldn’t resist taking pictures of the train — even though my original purpose was to enjoy the night view. Finally, I’m sharing a photo of Rainbow Bridge and Tokyo Tower at night. That was what I meant to focus on!

Have a good night.

Night view of Rainbow Bridge and Tokyo Tower

Hoshi-imo Train on the Minato Line

Hitachinaka Kaihin Railway KiHa100-40 “Hoshi-imo Train”

After enjoying the “Big Catch Cherry” blossoms at Nakane Station, I boarded the Minato Line once again. My next stop was Nakaminato, one of the best places for railfans to observe the diverse fleet of the Hitachinaka Kaihin Railway.

The moment I stepped off the train at Nakaminato Station, something unusual immediately caught my eye. Standing quietly in a corner of the station was a bright yellow diesel railcar that I had never seen before on this line. Take a look at the top photo. What could it be?

If you are thinking, “I’ve seen this railcar somewhere before on this blog,” you probably have a sharp eye for Japanese rolling stock. The answer is a KiHa100 series diesel railcar formerly operated by JR East.

Here is the story behind it. Hitachinaka Kaihin Railway recently acquired three second-hand diesel railcars from JR East. Two of them will replace aging vehicles currently in service. The third one, however, is destined for something more special — a new sightseeing train.

The bright yellow railcar in the photo is that very unit.

Its official designation is KiHa100-40, a member of the KiHa100 series. Interestingly, Hitachinaka Kaihin Railway decided to retain JR East’s original numbering. At the same time, the car received a new nickname:

“Wrapped Train of the Hoshi-imo Train Kingdom,” or simply the Hoshi-imo Train.

So what exactly is Hoshi-imo?

Hoshi-imo is a traditional local specialty made from steamed and dried sweet potatoes. With no artificial sweeteners, it is a simple yet naturally sweet and chewy snack that has long been popular in this region. In a fun touch, the side of the train even features the recipe for Hoshi-imo, complete with a short English explanation for visitors (see the photo below).

A train that teaches you how to make a local snack — how cool is that?

According to a station staff member, the Hoshi-imo Train will soon enter service as a sightseeing train on the Minato Line. Perhaps passengers will even be able to enjoy some freshly prepared Hoshi-imo on board. That would certainly make the ride even more memorable.

From a technical standpoint, the KiHa100 series is a compact 16.5-meter diesel hydraulic railcar that first appeared on JR East lines in 1990. A total of 64 cars were built by Niigata Tekko and Fuji Heavy Industries, each powered by a 243 kW diesel engine.

The particular unit seen here, KiHa100-40, was built in 1991 and transferred to Hitachinaka Kaihin Railway in 2024.

I’m already looking forward to riding the Hoshi-imo Train on my next visit to Nakaminato.

Hoshi-imo themed design on the side of the train

Early Blooming Cherry Blossoms on the Minato Line

Big Catch Cherry and a diesel railcar at Nakane Station on the Minato Line

It has already been ten years since my last visit to the Minato Line. A full decade has gone by in the blink of an eye, and I felt it was finally time to revisit this beloved local line. Here, I’d like to share some observations from this latest trip.

■ What is the Minato Line?

The Minato Line is a local railway operated by the Hitachinaka Kaihin Railway Company in Ibaraki Prefecture, about 120 km northeast of Tokyo. Running between Katsuta and Ajigaura, the line covers 14.3 km with 11 stations. Katsuta provides an important connection to the JR East Jōban Line.

As many railway fans know, the entire line is a non-electrified single track, giving it that distinctive rural local-line charm.

■ A Glimpse of Spring Along the Line

Before diving into rolling stock updates, let me first share a seasonal highlight. The photos show a train arriving at Nakane Station, framed by early-blooming cherry blossoms. The combination of a diesel railcar and soft pink petals is enough to lift any railway enthusiast’s spirits.

These blossoms are known locally as Tairyo-zakura (“Big Catch Cherry”). Since the line passes through Nakaminato, a well-known fishing port, the name reflects the community’s wish for a bountiful catch. Their vivid pink hue reminds me of a sea bream—a fitting symbol for the coastal region.

■ Rolling Stock Notes: KiHa 3710 Series

Naturally, a proper railway post wouldn’t be complete without a look at the trains themselves.

The railcar pictured at Nakane Station is Unit 2 of the KiHa 3710 series. This diesel railcar features an 18.5-meter-long body with longitudinal seating, powered by a 243 kW diesel engine.

The KiHa 3710 series consists of two units: Unit 1 introduced in 1995 and Unit 2 in 1998. Currently, Unit 2 sports a full-body advertisement wrap for Komatsu, known worldwide for its construction, mining and forestry-related heavy equipment.

To be continued…

Unit 2 of the KiHa 3710-series diesel railcar departing Nakane Station

Related link:

・Official website: Hitachinaka Kaihin Railway (in Japanese)

Final Chapter of Dr. Yellow

Set T-5 of the 923 series EMU, Dr. Yellow, arriving at Tokyo Station

Do you remember when I first introduced the Dr. Yellow train running on the Tokaido–Sanyo Shinkansen back in 2017? Well, I finally had the chance to photograph it again—so today, I’d love to share that moment with you.

But first—what exactly is Dr. Yellow?

Dr. Yellow is a high-speed inspection train whose official designation is the 923 series EMU. It entered service in 2000, replacing its predecessor, the 922 series. Only two sets were ever built—14 cars in total—manufactured by Hitachi and Nippon Sharyo. One set (T-4) belonged to JR Central, and the other (T-5) is owned by JR West.

Its job? To inspect tracks, signals, telecommunications, and power systems—all while speeding down the Shinkansen lines. Its body is based on the 700 series design, and the bright yellow color helps distinguish it from passenger trains.

So… what’s the latest on Dr. Yellow?

Recently, I learned that JR Central’s T-4 set has already been retired. That means only one Dr. Yellow remains in operation today: the T-5 set.

Take a look at the photo above—that’s the last surviving Dr. Yellow, arriving at Tokyo Station. When I was there, more than twenty rail fans had already gathered, cameras poised and ready. And it wasn’t just the usual adult male rail enthusiasts—there were women, kids, and even international fans. Dr. Yellow really brings people together.

Even though JR Central and JR West never publish Dr. Yellow’s schedule, sightings spread instantly on social media, drawing crowds to stations like a modern-day treasure hunt.

So, what’s next for Dr. Yellow?

According to JR West, the remaining T-5 set will be retired in 2027 or later. After that, inspection duties will be carried out by standard Shinkansen—specifically the N700S series—equipped with advanced measuring devices, image-processing systems, and AI technologies.

Technology moves quickly. It’s impressive… and a little bittersweet.

Dr. Yellow’s final chapter has already begun.

Dr. Yellow (left) and the N700A series EMU (right) at Tokyo Station

Related link:

・Official information: JR West’s railway maintenance vehicles (in Japanese)

Winter Travel to the Tohoku Region: Part 5

Abukuma Express AB900 series EMU (Set AB-7) approaching

Let’s pick up where we left off.

After enjoying the snow-covered landscape along the Tsugaru Railway Line, we went to Hirosaki Station in Aomori Prefecture, where the Train Suite Shiki-shima cruise train was waiting for us. This winter journey was full of unforgettable moments—beautiful scenery, local culture, and regional cuisine—but I’ll save those stories for another time. For now, let’s get back to the railway highlights.

On the return run to Tokyo, I spent quite a bit of time enjoying the forward view. The observation car was nearly empty, so I practically had the place to myself. For railfans, this spot is pure heaven.

One particularly memorable moment occurred near Tsukinoki Station in Miyagi Prefecture. Take a look at the top photo first. A green train was approaching in the distance. Any guesses?

It turned out to be a train of the Abukuma Express. As mentioned in my post from 2024, Abukuma Express is a regional railway operating between Fukushima and Tsukinoki, with a total route length of 54.9 km.

Interestingly, the tracks of Abukuma Express and JR East’s Tohoku Main Line run parallel for only about one kilometer near Tsukinoki Station. Despite that short shared stretch, Shiki-shima happened to meet an Abukuma Express train right there. Even better, it was the green AB900 series trainset (Set AB-7), which I had never seen before. What a lucky encounter!

Before wrapping up this post, let me share one more highlight from the journey. After departing Utsunomiya Station in Tochigi Prefecture, passengers were treated to a live jazz performance in the lounge car (see the photo below).

Utsunomiya is known in Japan as a “city of jazz,” and the musicians actually boarded the train at Utsunomiya Station. Their performance created a wonderful atmosphere on board. It was a refreshing and memorable way to end the day’s journey.

Live jazz performance in the lounge car of the Train Suite Shiki-shima

Related link:

・JR East official video: Making movie of the Shiki-shima theme music