The Troll Pits of Hextor (5e)

Welcome.

"Troll Pits" in this instance signifies "pits in which Trolls are kept".

These pits are vast depressions in the black volcanic soil of Mordor.  Tirelessly dug by multitudes of Orcs, they reach deep and wide, to the point of almost becoming valleys.

At the bottom of each of these great pits, the mighty Trolls are kept, where for the time being they are left to their own devices.

Due to the soil being like a kind of black sand, always sifting, affording no purchase to climbers, there is no danger that the Trolls will ever crawl up out of the pits in order to wreak havoc above on their own.

But once the Trolls are finally ready to be unleashed as part of the Dark Lord Sauron's army, He will exert His Almighty Will upon them and there will be no need to confine them anymore.

Then shall the Orcs exalt the Trolls and sing their praises; and they shall throw great ropes and chains down unto them, that they might climb up out of the pits in order to wreak havoc above under His Almighty Will.

And then shall all of Middle-earth tremble in the path of their awakened fury.