Board Thread:Suggestions forum/@comment-26296200-20150529141809

as most of you know beleraind was a land east of the blue mountains and lindon but it was completely destroyed in the war of the warth and sank into the ocean what was left was the western isles like toifuin I think when you add the first age beleraind should be part of middle earth because it was there in the first age but not the second or tihrd. I think as the major quest storyline ends like after you beat mordor and when the ring is destroyed you should progress into the 4th age and midway through 4th age storyline beleraind should rise from the sea because it would be cannon or half-cannon because Galadriel's last words to treebeard at their departing at isenguard were  "Not in Middle-earth, nor until the lands that lie under the wave are lifted up again. Then in the willow-meads of Tasarinan we may meet in the spring. Farewell!" this suggests that beleraind may be recovered from the sea possibly after the dagor dagorath in arda had healed.

I got this information from the one ring wikia so its cannon 