This site is well worth the extreme difficulty of reaching it (three ferrys and an open boat with an outboard motor mimimum). Ferry 1: to mainland Orkney, Ferry 2: Kirkwall – Westray, Ferry 3: Westray – Papa Westray, Small Boat: Papa Westray (Papay) – Holm of Papay. Enquire at the Youth Hostel/Co-op for boat trip (a few pounds).
Site is very visable from Papa Westray – looks like a submarine due to upstanding concrete entrance through roof. Roof has been restored with concrete and glass bricks. Muddy floor is covered in plastic sheets, which is useful but ugly.
Worth visiting for the sheer number of antechambers (14 or so from memory). “Eyebrow carvings” are less impressive in reality than in photos.
There is also another, round chambered cairn at the north of the Holm, which is less well preserved (ground plan only) but easily found, and worth visiting.
Incidently, there is a natural rock bridge in the cliffs on the south end of the holm.
We were on Papa Westray for several days and never made it to Papa Holm but, walking the East coast, were able to scrutinise the landscape context from several angles. The South Wick area with St Tredwells Isle with chapel, broch, cairn & souterrain remains, a nearby ancient water mill and excellent landing cove all within short walking distance........wove all sorts of pictures from the past, for me. Even the name "St Tredwell" is said by some authorities to have pagan origins.