Those of Moher and Dover are well-known (6)
I believe the answer is:
cliffs
(Other definitions for cliffs that I've seen before include "High steep rocks" , "High, steep rockfaces" , "Dover has white ones" , "Steep rock faces" , "Precipices" .)
I believe the answer is:
cliffs
(Other definitions for cliffs that I've seen before include "High steep rocks" , "High, steep rockfaces" , "Dover has white ones" , "Steep rock faces" , "Precipices" .)