In the text, Heorot is described as helearna maest, "the best of halls." It was deliberately crafted to be the epitome of what a mead-hall should be, with the work of many people from different nations contributing to this "folcstede fraetwan," or "hall of folk." Heorot is the center of the community and from its inception has been a symbol of togetherness. It is "high and horn-gabled," but it is not its physical beauty which awakens Grendel's displeasure. Rather, it is the "noises of revelry" from within the hall which make Grendel, sé þe in þýstrum bád ("he who dwelled in darkness"), feel inclined to attack. The defining feature of Heorot, then, is that it is a place where people come together to enjoy themselves, a place where boasts are made and rings exchanged, the symbols of pacts and relationships in Anglo-Saxon communities. Grendel is excluded from this, dwelling alone in darkness.
Grendel is an "infamous stalker in the marshes," "fen ond faesten"—the desolate stronghold of the fens is his home. The idea of "the fens" recurs in Old English poetry as representative of the hinterlands outside of the warm glow of acceptable society. As an outcast living in these hinterlands, Grendel is "in darkness" in contrast to the light of Heorot, and he is alone by contrast to those who enjoy togetherness in Heorot.
In describing Grendel's home, the poet actually says "men ne cunnon / hwyder helrunan / hwyrftum scríþað," which means "nobody knows where hellish enigmas like this make their homes." However, the poet is certainly sure that wherever Grendel's home is, it is not like Heorot. After Beowulf has wounded him, Grendel flees "to seek his joyless abode."