Before NEXT, you could only build your base in a pre-defined area. You could recognise it by the circular building, and the nicely flattened circular area of land.
NEXT changed all that. You could build your base anywhere, and we all did. Of course, it’s not without problems, because the terrain is no longer flattened for you, and if you do flatten it, it tends to come back, and poke through your buildings. Still, you learn to build on stilts.
So (call me a fool for not realising this), it has come as something of a surprise to me to discover that the old pre-built bases still exist.
They no longer have the circular building - they just have a blue base computer with a light on top. But they do have the large circular area of pre-flattened land. Which is very handy. They look like this:
So, if you’re having trouble with terrain invading your bases, there is an answer. The old ones are still there.