Wales, mostly. Which isn't in England. So, Cornwall, Dorset, Devon, Somerset, mostly
really? "of" in this context can also mean "outside of" as in East of Eden
Isn't Ireland west of England? go a bit further and you'll get to Canada!
There is a University of the West of England. (But nobody can find it.) http://www.uwe.ac.uk
Avalon means apple. New York is called 'The Big Apple'. When King Arthur died he went to Avalon which was to the west of England. So is New York. Does this mean that Avalon was New York city and that that's where King Arthur ended up? I seem to remember a move called 'the Fisher King' where Robin Williams played 'King Arthur' and was running around Manhattan. something like that.
On the other hand, you might find that Avalon is really called Afallon. A single "f" in Welsh is pronounced as a "v" in English. By the way, the word "apple" is written as "afal" in Welsh. This was part of our culture many centuries before <insert-discoverer-of-your-choice> found America.
Here's an interesting reference: http://www.caerleon.net/history/arthur/page3.htm
First somebody brought up Tolkien's languages, now it's King Arthur. Not many people outside Britain seem to know much about Wales but it's surprising how our culture gets around by stealth. (By the way, Dubya is on record as having asked Charlotte Church what state she is from, after she told him she was from Wales.)
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