How was this dramatic mountain landscape look created, and are the fog/road real?

Really flattered to learn that so much discussion is going on about my photograph. I'd like to pitch in of course and tell you exactly what I did with this photo.

Here, firstly, is the unprocessed photo, that you may compare with the processed one below. This should answer many questions at once:

You get this view of Mt. Untersberg from around the middle of the Hellbrunner Strasse stretch. So yes, this is a real setting and no manipulation of the landscape etc. has been made in post-processing, except getting rid of some birds on the path with clone stamp. I hope that answers questions 3 and 4 of the OP.

However, the image still lacked detail and contrast, so I used my usual method to get a bit more action going. This involves copying it into more layers in Photoshop, tweak the levels adjustment to get the exposure of different parts right, and use brushes on masks to make those parts visible. I also use some general vibrance, photo filter adjustments etc. There's another trick I sometimes use for a glowing look depending on the photo, which I did for the field here. It is to use a blurred layer copy on top set to 'soft light' or 'overlay'.

I have written down a blog post with the exact details of how I achieve these effects.

Okay, now for the other two questions:

Q.1: You are quite right that the halo around the mountains was an artificial collateral of trying to increase the contrast of the sky.

Q.2: The 'fog' at the base was also brought out using the technique I mentioned along with some photo filters adjustment (again, I use it only on localized region on copied layers, then make it visible with soft brushes on masks). This often causes a difference between the lighting conditions of various objects (here the sky is cool, the mountains look warm) that can be picked up by careful eyes such as yours, and which my short foray into post-processing doesn't yet allow me to remedy.