In the underground city, generally speaking, the further down you go, the larger the floor area becomes.
According to joint statistics from the guild and numerous familias, the area of the 5th floor of the underground city is already comparable to the central plaza in front of Babel Tower, while the area of the 40th floor is equivalent to the entire expanse of the city of Orario, incredibly spacious.
It is precisely because of this that a town appears on a safe floor like the 18th level.
If the area were insufficient, a town would not be established; it is because the underground city is spacious enough, grand enough, that all sorts of miracles happen successively.
Of course, before the 18th floor, no matter how spacious each floor may be, the area is still limited and cannot accommodate too many people.
