Board Thread:Off Topic/@comment-216.65.166.241-20130808065946/@comment-90.206.110.178-20160815004237

While, yes, Skuldafn could have been better implemented by Bethesda, it is explicitly stated during the quest, by NPCs in-game, that Skuldafn is a one-time thing and you won't be able to (without cheating) return. Nakhriin and the word wall are directly in the Dragonborn's path to the portal.