Rather Large Areas

With the idea of an open area similar to the Wastelands in Jak 3 in mind, would it be possible to create something like this in UE4 without use of procedural generation?

Related note: What are size limitations in UE4 for the landscapes/worlds/field(whatever you wish to call them), as I was thinking of a world that was roughly 120 square km.

It’s possible to create large world without procedural generation. You may want to read this UE4 documentation to get a clear picture of UE4 open world capability.