Atomic Heart map and how to open it

How big is the Atomic Heart map? That's a much more difficult question to answer than it may seem at first, because Atomic Heart doesn't have just one big open world - it's split into lots of different regions and you can't just high-tail it from one place to the next willy-nilly.
So while Atomic Heart is technically an open world game, you'll soon learn that you won't be doing much exploration off the beaten track - though there are some things to find if you do venture away from the usual Atomic Heart bosses. Here's what you need to know about the Atomic Heart map, along with whether there's an Atomic Heart fast travel mechanic.
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