1987 · Great Sphinx, Giza, Egypt
Cavities under the Sphinx
The ruined Sphinx Temple in front of the Great Sphinx at Giza, with the pyramids of Khafre (left) and Khufu behind (2009). · someone10x / Flickr, via Wikimedia Commons
When1987–1991
WhereGreat Sphinx, Giza, Egypt
Two surveys around the Great Sphinx reported underground spaces: a Waseda University electromagnetic survey in 1987 (a tunnel under the body, cavities by the hind paws) and a 1991 seismic survey by Thomas Dobecki with Robert Schoch and John Anthony West (a cavity in front of the left paw). The same 1991 work fed Schoch's argument for an older Sphinx. Neither spot has been dug.
How plausible · High
Two independent teams with different methods report cavities under the Sphinx; never excavated.
- ●●Access Survey teams on site.
- ●●No gain sought Academic surveys.
- ●●Character record Waseda University and a professional geophysicist.
- ●●Independent convergence Electromagnetic (1987) and seismic (1991) surveys agree independently.
- ●●Physical traces or official reaction Instrument readings.
- ●○Restraint Report cavities, not their use.
Against
- −Contradicted by an insider The readings are contested; void readings at the Great Pyramid didn't hold up on drilling.
Plausibility weighs how well an account fits where secrecy hides the documents by design, so missing records never count against it. Strength measures what is documented. Assessed 2026-10-23.
Claims
Electromagnetic sounding showed a north-south tunnel under the Sphinx and cavities near its hind paws.firsthandSourced, unconfirmedWaseda University team (Sakuji Yoshimura, 1987)
Seismic refraction and reflection showed a cavity in front of the left paw and along the south flank.firsthandSourced, unconfirmedThomas Dobecki with Robert Schoch and John Anthony West (1991)
A 1986 French microgravimetry survey of the Great Pyramid flagged voids, but test drilling at those spots found no chamber.firsthandOn the recordEDF / CPGF (Dormion and Goidin), via NOVA
Where
Great Sphinx, Giza, Egypt
30.0°N 31.1°E
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