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Sunken City · Advanced dives

The Yonaguni Monument

Age disputed · 5 to 25 m, Off Yonaguni Island, Okinawa, Japan
ACCESSIBLE
Evidence status: Historical tradition. no documented source (historical tradition); legal status unknown (manual verification recommended). This account is presented as historical tradition, not verified fact. Manual verification recommended. Repository evidence: 0 sources · 0 timeline events · 0 media items · legal unknown · view on the Map Evidence on file: historical tradition

The Yonaguni Monument: still unexplained.

Terraces, channels, and right angles, city or geology, the sea won't say

The law of this ground: Open to divers via Yonaguni operators, strong currents demand advanced certification; take photographs, not opinions, as fact.
The subject
developing the photograph…
The manifest
Terraces, channels, and right angles, city or geology, the sea won't say
The account

Off Japan's last western island, a stone formation rises from twenty-five metres like a flooded ziggurat: terraces, flat planes, sharp corners, what some call a gate. One school says a sunken city ten thousand years old; another says the sandstone simply breaks that way. The current rips, the hammerheads school past in winter, and the argument continues at depth.

Leads, where the trail points now
  • A stepped rock formation off Yonaguni in Japan that some call a 10,000-year-old sunken structure and others read as natural sandstone fracturing.
  • No artifacts have ever been recovered from it, which favors the natural explanation; the open question is geological, not archaeological.
  • It is a popular dive site, so this is a thing to study underwater, not a treasure to lift.
What the record holds

What remains open

  • No period map of the site has surfaced.
  • No contemporary press coverage has been found.
What we know, and what we don't
Established

No documentary claim is yet established. The account rests on tradition.

Still open
  • No period map of the site has surfaced.
  • No contemporary press coverage has been found.
The evidence room

No documentary or visual exhibits have been located yet. The trail below and the open leads are where this dossier grows next — every exhibit that enters here carries a source.

Where the trail points now
  • A stepped rock formation off Yonaguni in Japan that some call a 10,000-year-old sunken structure and others read as natural sandstone fracturing.
  • No artifacts have ever been recovered from it, which favors the natural explanation; the open question is geological, not archaeological.
  • It is a popular dive site, so this is a thing to study underwater, not a treasure to lift.
  • Search Library of Congress + DPLA (IIIF) for period cartography of the site.
  • Run Chronicling America for dated newspaper mentions.
  • Query NARA for archival records tied to the site.

Have a source, a map, or a clipping? Add a lead and it enters the record with its citation.

Start the hunt here
The first leads, so no one walks in cold.
Sources and the record
Related case files

The full hunt kit

Starting brief, what's known and disputed, evidence timeline, source list, map card, coordinate-confidence and legal-access summaries, and a field checklist, free with a Fellowship account.

Latest Word From the Newswire

Context, not proof. The dossier's own sources remain the evidence record.

Checking the wire…

Chart position 24.435°, 122.935° (approx.) View on the Map