Not that deep 2 to 3 centimetre
The superlative form of the word "deep" is "deepest".
The foundations for the Eiffel tower are different for the east and south legs (contained in a 7-meter deep well) and the west and north pillars. The latter being very close to the river Seine, the foundation well had to go 22 meters deep. Details in link below:
The deepest ocean is 36,200ft deep
The Pacific Ocean has the deepest point in the Challanger Deep.
The merced river is about 5 ft deep at its deepest point.
Pretty Deep.
23cm deep
That is the correct spelling of "deepest" (most deep, or innermost).
The South Pacific Ocean is 35,797 feet deep at it's deepest point. This means that the deepest point is 10,911 meters deep.
8 inches
What is the deepest part of the worldโs oceans and how deep is it?
The World's deepest bellybutton is approximately 10' 7" deep. People have gotten lost and died in there!