How far from London can you see the skyglow?

Question

I went on a camping trip a while back, down to Land's End, Cornwall. We saw skyglow from something, and my friend was adamant that it was London. I'm highly skeptical that it was, but I'm just curious how far from London you could see it.

If you don't know what I'm referring to:

http://en.wikipedia.org/wiki/Sky_glow

Answer 1

In a sense you are both right.  The whole of Southern England is contaminated by skyglow.  The skyglow from Londion affect an area with a radius of up to 100km.  So unless you were more than 100km from London, part of the sky glow you saw was from London.  A lot of the rest of it was from other industrial souces in and around London.  It seems like it's getting impossible these days to get away from it.  

The entire area consisting of southern England, Netherlands, Belgium, west Germany, and northern France have a sky brightness of at least 2 to 4 times above normal (see above right). The only place in continental Europe where the sky can attain its natural darkness is in northern Scandinavia.

http://en.wikipedia.org/wiki/Light_pollu...