Board Thread:Lore Discussion/@comment-17087283-20131214225450/@comment-3186827-20131214230808

Not much is known. Lyg is basically a parallel version of Tamriel. It is called one of the "Adjacent Places". According to to author, it appears to be located on Nirn itself.

http://ladynerevar.tumblr.com/post/66412506492/the-continents-of-nirn-scaled-to-those-of-earth