Vacchagotta asks the Buddha how his teaching on the subject of rebirth differs from that of other teachers; for example, of Pūraṇa Kassapa. The Buddha explains that, according to his own teaching, rebirth comes only to a being who has fuel, the fuel being craving (S.iv.398 f).
The discussion arises out of a conversation which, according to Vacchagotta, took place among the wanderers (paribbājakā) in the Kutūhalasālā.¹
Buddhaghosa says (DA.ii.369; MA.ii.694) that there was no special place of that name; any place where discussions were held could be so called. See also D.i.179.
¹ A hall for recreation; kutūhala = excitement.