Fallout Cascadia mod to be larger than Far Harbor!
Far Harbor may be the biggest piece of DLC that Bethesda has ever created but that doesn't stop modders going one step further by creating something even larger.
Early look at Cascadia
Though it's a long long way out (years) the upcoming Fallout Cascadia mod will feature more quests and locations than Fallout 4’s Far Harbor. The mod is going to be set decades after the events of Fallout 4 and will be a standalone adventure that goes beyond the game.
They've been working on the mod for 6 months and have a team of 18 people behind it so while it's early on they have the drive to create something special. Follow the mods progress on the official site - http://falloutcascadia.tumblr.com/
Source: http://uk.ign.com/articles/2016/05/23/huge-fallout-4-fan-mod-will-be-bigger-than-far-harbor