(as) ancient/old as the hills
(as) bald as a coot
(as) bald as a cue ball
(as) blind as a bat
(as) clean as a whistle
(as) cool as a cucumber
(as) easy as ABC
(as) red as a beetroot
(as) stubborn as a mule
(as) thick as two short planks
(as) thin as a rake
(as) ugly as a toad
eat like a horse
like a duck to water
