its not blocked, it's hilly area. (probably traveling slower, seeing further)
I know it's perhaps not so clear, but I suppose the map will come with a legend/key for what the different areas are.
I needed a good way to represent hills, and I choose the dotted pattern. I have an alternate line pattern, or even other solutions at hand, so there is no problem to change them. I 
assume I have to adjust and do final changes later on anyway, so I hold and wait for feedback. There probably 
are bugs in it, although, it should not be... 

   I especially suspect changes when cities and villages are added. 
Also.. I should beautify the black lines representing cliffs.. 
Anyway, I'm open to input!