Updated: Oct 8, 2020
Apparently over the weekend someone leaked a sneak peek of the physical boxed copy of Night City. Though, at first glance it does look like it can be cramped but developers have mentioned many times that Cyberpunk is more centered around verticality of megastructures and possibly the ability to enter more building than past open world city games. To give a quick size comparison to the game we all love GTA V city of Los Santos 13.76 sq./Km and Cyberpunk's Night City is rumored to be right around 24 sq./Km.
The one unknown is that we don't know how much the verticality of the city plays a part in this open world, but with the hints from the CD Projekt Red devs it seems there will be plenty of area for you to explore without having to return to the same content multiple times like we have seen in past games like Borderlands.
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