profundity

The state of being profound; magnitude, gravity, or intensity.

The situation's profundity escaped most observers.

Deep intellect or insight.

Near-synonyms: brilliance, genius

Unfortunately, Andrew's colossal ego means people miss his profundity.

A great depth; a deep place.

Near-synonym: abyss

I delved the abyssal profundities of Neptune's realm.

Depth; the state of possessing great downwards extent.

[A] sharp-looking old dame, […] inhabited a "laigh [low] shop," anglicé [in English], a cellar, opening to the High-street by a strait and steep stair, at the bottom of which she sold tape, thread, needles, skeans of worsted, coarse linen cloth, and such feminine gear, to those who had the courage and skill to descend to the profundity of her dwelling, without falling headlong themselves, or throwing down any of the numerous articles which, piled on each side of the descent, indicated the profession of the trader below.