Just inside the entrance passage.
The passage section is the trapezoid shape that is very common in
prehistoric dry stone structures, the roof is lintelled.
There were originally alcoves in both sidewalls and it is said that even with
these recesses
there was no opening to the passages within the wall thickness.
We found this a little strange, as we could see light from the entrance way
shining through the
end of the northern passage between the stones of the wall.