What is the name of Odin's hall where fallen warriors feast?

Odin’s hall where fallen warriors feast is Valhalla.

In Norse mythology, Valhalla is a great hall in Asgard ruled by Odin. Valkyries choose many of those who die in battle and bring them there; these warriors are called the einherjar. They prepare for Ragnarök by fighting during the day, recovering from their wounds, and feasting afterward.

The Prose Edda describes the einherjar eating the boar Sæhrímnir, which is cooked each day and restored each night. They drink mead supplied by the goat Heiðrún, while Odin himself is said to live on wine and give his food to his wolves, Geri and Freki.

Valhalla is often confused with Fólkvangr, Freyja’s realm, because not every battle-dead warrior is said to go to Odin’s hall. Gladsheimr is another point of confusion: it is the broader hall or region in which Valhalla is located, not the usual name of the feasting hall itself. Helheim, meanwhile, is associated with the dead who do not enter these warrior afterlives.