Masakado-zuka: The Feared Burial Mound in Tokyo's Financial District

In the office buildings beside a small burial mound in central Tokyo, a rumour says staff arrange their desks so that no one sits with their back to the grave. Japan Today, an English-language news site, has reported this rumour, and it said plainly that many people call it made up while others insist it is true. Nothing confirms it. Still, the story shows how a burial mound for a warrior who died in 940 still makes people uneasy at the heart of Japan’s financial district.

Quick facts

• Verdict: Masakado-zuka is a real historic site. Its curse stories are traditional folklore that grew over centuries, long before the internet, and a preservation society that still exists looks after the site.
• Name: Masakado-zuka (将門塚), also called the kubizuka (head mound) of Taira no Masakado.
• Type: A legend attached to a real place: a burial mound and shrine.
• Commemorates: Taira no Masakado, a warrior who died in 940.
• Location: Otemachi, Tokyo, in the financial district in front of the Imperial Palace.
• Earliest confirmed curse record: 1923, the Ministry of Finance episode after the Great Kanto Earthquake.
• Where it spread: Tokyo. The stories grew mainly around government building projects on or near the site.

The legend

The story centres on Taira no Masakado, who died in 940, and the mound in present-day Otemachi that keeps his memory. English Wikipedia says the site once sat on a hill that jutted out into Tokyo Bay, long before the city grew up around it. A shrine was built at the mound. For generations, people have linked the care given to that shrine with the prosperity of Edo, the old name for Tokyo, and of the modern city. The belief is simple: honour Masakado and the city does well; neglect him and natural disasters and misfortune will follow.

The modern form of the legend is about disturbing the mound. After the Great Kanto Earthquake of 1923, the Ministry of Finance planned to put a temporary office on the site. Japanese Wikipedia reports that construction workers, ministry staff and the finance minister of the day then died one after another in unexplained ways. Rumours spread that Masakado’s curse was to blame. Later stories added more incidents: a lightning fire at the ministry, and accidents when post-war planners wanted to redevelop the area. Each is told as more proof that the mound should be left alone.

The real place today

English Wikipedia says the mound is still carefully looked after, even though it sits on some of Tokyo’s most valuable land, among the financial district’s office blocks in front of the Imperial Palace. A preservation society manages it. The society says it was formally founded in July 1960 to honour Masakado, console his spirit and preserve the mound, and that it became a general incorporated association in November 2023.

The site has recently been renovated. Japanese Wikipedia records a sixth renovation from November 2020 to the end of April 2021. The preservation society says the project took about three years from the first discussions in spring 2018 to completion in spring 2021: two years of planning talks, six months of detailed design and six months of building work. The society also says the work was timed to finish on the 1082nd anniversary of Masakado’s death.

The society says it had two aims: to shed the frightening image the mound had gained in more recent centuries, and to bring back the friendlier image of Masakado that ordinary people held in the Edo period. The work also made the grounds safer and easier to manage. It was planned alongside the redevelopment of the surrounding Otemachi district, and a new slope was added so that more people could visit.

Documented events

The ministry site. Japan’s National Tax Agency, whose predecessors include the Ministry of Finance, says the ministry set up its offices in 1871 on the former estate of the Sakai family, lords of the Himeji domain, at Kandabashi. The mound stood on those grounds. After the 1923 earthquake, the agency says, the ministry tried to demolish the mound and build a temporary office there.

Deaths and a memorial rite. Japanese Wikipedia says the engineer in charge of construction for the ministry died in 1927, four years after construction began, and that the ministry held a memorial rite for Masakado’s spirit in March 1928.

The 1940 fire. Japanese Wikipedia says a fire caused by lightning destroyed the Ministry of Finance building in 1940. The National Tax Agency says disaster countermeasures were put in place at government buildings around the mound in June 1940, after the fire.

After the war. Japanese Wikipedia says that when the US military planned to redevelop the Marunouchi and Otemachi area, a series of unexplained accidents followed. In one, a bulldozer overturned and its driver was killed. The plan was dropped, helped by a petition from the head of the local neighbourhood association. The preservation society describes the same period from its side: its post-war preservation work began when a local elder petitioned the occupation authorities (GHQ) and stopped the mound from being destroyed.

What is contested

The earliest-record caveat above applies here. Wikipedia and Japan Today disagree on how many people died and when. Japan Today names a finance minister and construction company executives among the dead and gives a total of 14. The National Tax Agency website, which Japan Today mentions, confirms only the building plan and the 1940 countermeasures; its material listed here gives no death toll. Japanese Wikipedia is more careful and reports the deaths only as things said to have happened. The deaths, the fire and the post-war accidents are documented to different degrees, but no source shows that a curse caused any of them. The link is a matter of belief.

The desk rumour from the opening is weaker still. Japan Today presents it only as gossip that many people dismiss, and no source confirms that any company actually arranges its desks this way.

The preservation society’s own account shows the tension inside the legend. The mound is said to punish neglect, yet its caretakers set out in the latest renovation to replace that frightening image with a friendlier one.

A note for visitors

Masakado-zuka is an active place of memorial in a working business district, so please visit quietly and respectfully during the day, as you would at any shrine. Don’t treat it as a spot for thrill-seeking or late-night ghost hunting, and be considerate of the office workers and staff around it.

How it is discussed in Japan today

Ocsoku, a Japanese occult blog, has covered the mound in 5 posts between 2015 and 2026.