Answer:
I am a path between high natural masses; remove the first letter to get a path between man-made masses.
I hold two meanings. With one I may be broken with the other I hold on.
When I point up, it's bright. When I point down, it's dark. What am I?
I am a portal to another world which you cannot enter. Only you can see me but I can't see you.
What can travel all around the world without leaving its corner?
Why is the letter B always cool?