At the bottom of the southern passage.
There is a kind of nexus here, the NW passage runs off to the left, and the
lintelled
entrance to the rab-cut chamber is in the centre of the picture.
The roof structure at this point is very complex, part of it can be seen in this
shot. Some of the
roof stones here did not seem to be supported very well, but as they've
been there for
about two thousand years, so we assumed they must be pretty stable.