The deepest place in the ocean is about 7 miles down the Mariana trench in the Pacific Ocean... I think.
Henry Ford
That's one I can think of.
Maybe Albert Einstein but I don't know if they'll accept him.
"We had passed through long walls of piled skeletons, with casks and puncheons intermingling, into the inmost recesses of the catacombs."
"We are below the river's bed. The drops of moisture trickle among the bones."
These are some sentences that give us the creepy setting that makes for an eerie mood.