I have uploaded the file
to the Japan files at
showing how this gigantic dolmen,
(the largest so-called "corridor tomb" in Japan,
so-called because it is so large that one can walk within it)
marks the brightest star in Cassiopeia,
the star Shedar
also called Schebar - whence Ishibutai ? i.e. ca-SSIOPEIA) -
in the goedetic survey.
I think the major stones of this dolmen represent the five major
stars of Cassiopeia (though I have also considered whether these
stones might mark the five major stars of Cepheus).
Since ishi- means stone in Japanese, then the root here might
be "butai", which means "foundation, stage", perhaps a case for
Cepheus. However, since ishi- is usually put at the end of terms to
mean "stone", the ishi here might not mean stone at all originally
and Ishibutai might be a variant of Schebar, the alpha star of
Cassiopeia, which it appears to mark.
Hence, although the stars of Cepheus were also considered, I have
opted for Cassiopeia due to the Cassiopeia-shape formed by the
location of sites on the ground at Asuka - see asukamap.gif - site
locations which appear clearly to mark Cassiopeia.