One thing that's amazing about Britain -- in this case, Scotland -- is how many really old things dot the landscape about which nobody actually knows much at all. This is one example. On our way south from Edzell we stopped at a tiny turnoff in the midst of a moor and read these explanations . The countryside was, well, forbidding. We decided to check one of the "Catherthuns" out, chose the white for no reason we could think of, and started up the longish walk up , marvelling at the dense forestation (remembering what Samuel Johnson said about trees in Scotland). Soon we were above the outer "walls" and pretty much everything else, too. It was amazing to think how long ago this had all been put here, and to speculate about what they might have had in mind.