Montezuma's Tower at Garden of the Gods is pretty skinny, at least in one dimension.
By toddgordon From: Joshua Tree, California Nov 9, 2007
I've done both Montezuma's and Cleo......Cleo is MUCH skinnier;....on the summit, you straddle the rock;...one leg on either side;....it's rather gripping......it's only strength is that it is basically a fin of rock.....the last pitch, the rock is 6-10 feet thick the whole pitch......it's wild!