I have a problem. I found this cave all the way in the SE corner, east past the pond and waterfall, and circle up a slope, climb some steps. There's some ruins and off to the right from when you enter there's a small curving path down into a cave.

When I first got there, there was what seemed like an Aardable wall, but Aard didn't work. So I figured my Aard isn't powerful enough yet. Next level up, I improved my Aard and went back. Lo and behold, the wall is no longer there... except it's still there. I can now see freely into the cave/ruin down a drop, but "drop down" doesn't appear, making Geralt walk up against essentially an invisible wall.

Anyone understand what this is? And how to solve it?

You'll get there later in the story. Don't want to spoil too much so i'll leave it at that.

So it's just a bug than, that hopefully gets resolved when I'm supposed to get there? Not liking the linearity, or the bug here.

It's not a bug. It's by design. The story brings you into there later. I was also frustrated that I couldn't get through when I first found it.

It's an area that you end up in later on in the story. Right now you can't do anything to the wall. I will say this. At some point you have the option to take Triss on a quest. Do that to fully experience what is behind the wall.

Again: the wall is gone, but I can't get passed anyway.

Yes I had that same "bug". I could even see a lootable chest inside. But as others have said, you can just safely ignore it and move on with the story and you'll eventually get there.

Ah, sorry. I misread that. Yes, that's a bug. But as noted, don't worry. You'll get down there later and everything should be fine.

Whattya mean there's nothing down there? The session with Triss is quite something!

LOL

Funny how you need a improved Aard to break that wall, while Roche just ragepunch through it with bare hands.

Roche is Temeria's Chuck Norris.