This one was current at Legion
https://www.mmo-champion.com/threads...Map-Comparison
I think BfA probably is about large as WoD with Mechagon and Naz'jatar
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Something to note is that these days elevations can actually be used for gameplay. Up until MoP, most of the terrain used for elevation in WoW was simply map extrusions upward. They didn't really have ledges or structure on them. Starting with MoP but more clearly from Legion and after, mountains are no longer empty terrain; they can be places you adventure. I think the intent with Dragonriding is to build up on exploration. Before this element, exploration achievements were really mostly for collectors, requiring a lot of platforming (in a game that is very poorly designed for platform gameplay) and use of gliders and toys. With Dragonriding exploration is effectively progression. So the map will be designed to have areas that are temporarily inaccessible, not to fill in the space and hide easter eggs but so as to be made accessible organically (instead of binary by unlocking flight like TBC, Wrath and MoP did)
By this I mean to say, the map is likely to be used to a much greater extent than it was with Northrend. But also, far less will be accessible at launch unless you push the limits of what Dragonriding can do. This is interesting as well. In the past we have managed to get past Blizzard's intended map space by creative use of movement abilities. In an expac that will feature crafting as almost a pillar, people who manage to access areas early get much better access to gathering materials. Exploration will be a competitive thing in DF.