The dungeon in the valley, which lies on the opposite side of the “field full of folk” from the castle on the hill, symbolizes Hell. Holy Church explains to Will that the dungeon is governed by Wrong and was established when the prideful Lucifer disobeyed God and was cast out of Heaven and flung as far down as possible, where he would be forced to stay. A particularly low-lying place on earth is a valley, revealing the connection between the dungeon in the valley and Hell. Since humankind exists in between the castle and the dungeon, their lives on earth dictate whether they will earn Heaven or be sent to Hell.
Dungeon in the Valley Quotes in Piers Plowman
I saw a tower on a hill-top, trimly built,
A deep dale beneath, a dungeon tower in it,
With ditches deep and dark and dreadful to look at.
A fair field full of folk I found between them,
Of human being of all sorts, the high and the low…