In reply to nikoid:
Interesting. I always assumed Google Earth was almost exclusively satellite images but it seems you're right. A bit of Googling soon told me that it's a real mix of satellite and old-school aerial photography, and in this specific case the copyright info suggests aerial. Thanks, your pedantry was interesting.
Correction: I was looking at Google Maps rather than Google Earth. Can't see any similar info about data source in Google Earth. But holy cow, it's incredible that Google has 3D renders of some obscure boulders in a field in Wales.
Post edited at 19:45