Am also on a map since launch. Not certain if or how one can pull a date of when it was created. That info may not be retained.

If I ever lost the ability to play this map it would likely sunset Valheim for me. There is no way I can replicate what I've built, the "lived in" feeling is not something easily rebuilt. That being said I've yet to encounter any reason to move worlds, at a minimum I raid "resource", worlds for iron and such.