Obviously not, but it was said that the underworld has a "
beginning" and is made up of 4 spheres, 8 prisons, 3 valleys and 10 pits. And these structures make up the underworld. Although the scan again says that it is infinite, it seems strange to me that it has a beginning and an end, and a finite amount of structures make up its structure, unless the 4 spheres, 8 prisons, etc., are structures of infinite size, although it does not seem very feasible that the protagonists have traveled an infinite distance.