The doorway to the passage in the main
chamber.
We are looking SE through the doorway along the entire length of the passage,
the sunlight on the external walls neatly marks
the extent of the outer passage section, the roofed section below the cairn core
bring in shadow. The "horizon" seen through the passage
is the top of the modern steps giving access to the passage, as the external
grassed platform area is at least 1m above this, it is easy to
see that it would have completely blocked the passage when intact.
(ranging pole 1m).