This inscription on the wall is the first clue and one of the biggest foreshadowing done by the Developers of the game.
This inscription literally screams, 'Leave' if you put your ear on it and try to listen to it carefully.
The reason being that the creator of the inscription wanted whoever came later to not go deeper into the forgotten city as it has that monstrosity sealed inside it.
If not for the fact that Jareth took the help of the 'Laws' of the world and killed Konda in one-shot, that beast would have proved to be a very troublesome foe.
Its rampage would have never ended and it would have become the cause of death for millions of people.
'And after this corridor is the path...'
Jareth stepped forward and arrived on an open balcony like place located two stories high in a massive empty hall.
The hall was made up of the same glowing stones and there was miasmic mud filled in the hall.
