
There’s one level in this underground dungeon that can only be seen, but not accessed, by the public.
“There’s something that’s been bothering me on my commute, so could you please look into it?”
That was the message our Japanese team received from a reader recently, and it immediately piqued our interest. The message went on to reveal that at Korakuen Station in Tokyo, on the way from the Marunouchi Line to the Namboku Line, there’s an elevator with a button for a floor labelled as “B3”. Due to the setup of the station platforms, however, the floor doesn’t seem to make sense, but with the reader feeling too timid to press the button, they asked our team of reporters to investigate.
▼ So we headed out to Korakuen Station to visit the mystery floor.
After arriving, we walked along the Marunouchi Line platform, where we noticed a wall mural that resembled a castle from Dragon Quest. This seemed like an apt artwork for our adventure, but it also made us fear that difficulties and dangers might lie ahead.
Japanese train stations are so vast they’re often referred to as dungeons, and this mural seemed to be challenging us to push through to the final stage, defeat the boss, and rescue the princess.
▼ Feeling emboldened, we scanned the signboard and headed to the elevator.
▼ It didn’t take us long to reach the lift, which looked like any other ordinary elevator.
The Marunouchi Line is located on two above-ground floors, while the Namboku Line is located on six underground floors. With a difference in elevation of approximately 41 metres (134 feet), these are two of the largest subway lines in Tokyo.
Stepping into the elevator on the B1 level, we looked at the control panel, where we saw buttons for B1, marked “改札階” (“Ticket Gate Floor”), B5 (“都営線連絡階” [“Toei Subway Connecting Floor”]) and B6 (“ホーム階” [“Platform Floor”]). This was the same as the floor listing on the sign posted outside the lift when he got in, but inside, there was also an unmentioned “B3” level, which unlike the other levels, had no explanation next to it.
Finger quivering, we reached out to press the B3 button. However, after pressing it, it refused to light up, and what’s more, it triggered an announcement, with a calm-sounding pre-recorded voice saying: “No stopping on that floor”.
With other passengers in the elevator, the announcement hung in the air, creating an awkward moment. We could feel everyone’s eyes on our back, as if they were wondering why we’d pressed the button, but our embarrassment was soon forgotten as the lift began its descent.
▼ Camera poised to capture images of the mystery floor, we shot this video of the B3 level.
As indicated by the announcement, the elevator didn’t stop on this floor, and from what we could see of it, it didn’t appear to be intended for public use. Although it was brightly lit, there was no sign of life there, making it seem like a foreboding area in a zombie game, where the undead might burst through the door at any moment.
Looking closer at the sign on the door reveals the reason for its existence, as we could make out the words “変電設備” (“Electrical Substation Equipment“). Substations are facilities that convert high-voltage electricity sent from the power company into a voltage that can be used at stations and on trains, so the B3 level appears to be dedicated to equipment that supports the underground workings of the station. Stations consume a huge amount of electricity, running the subway, operating the lights and escalators…and the beating heart of it all is housed on the mystery B3 floor.
While ordinary members of the public aren’t able to access this level, it does need to be accessed by maintenance workers, who likely have a way of bypassing the normal controls, either through a special key, code or prior permission from station staff, hence the existence of the B3 button.
Being able to see, but not access, the floor does give it a mysterious allure for people using this lift. It’s just one of the many mysteries you’ll find inside Japanese train stations, like the secret stairs at Tokyo Station.
Photos ©SoraNews24
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[ Read in Japanese ]










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