One could be forgiven for thinking Yes Tor, almost the highest point in SW England,
was an old ruined city from the way the low evening light is picking out patterns in the granite clitter.
I seem to remember someone telling me those contours were caused by 'permafrost creep' or solifluction
in the peri-glacial conditions back in the Ice Age.
A similar periglacial freeze/thaw process is thought to have caused the hummocky terrain during
the Holocene period after the ice melted on some of the flatter parts of the high moor,
for example around the easily accessible Cox Tor
The vegetation-covered humps, which are about 50cm high, are called "thufurs."
An excellent resource to find out more is at:
https://adriancolston.wordpress.com/2014/12/16/what-are-these-bumps-on-the-moor/