Do you think the story of Arthur(the king of Camelot)is myth or fact,and why?

The best version I've read is that Arthur was some sort of late Roman
Count who scrapped with the invading Saxons. A novel by Alfred Duggan,
who also wrote history books.

Normally there is a grain of truth in myths.

The real clincher is that 'chivalry', castles and the weoponry they
were supposed to have used simply were not around in the dark ages in
Britain (ie: after the Romans left Britain (about 400 AD) until about
800 AD when things started getting recorded again).
They all came with the Normans.

During that period, things were a bit primitive in Britain.

If one envisages the 'knights' living in Roman ruins or wooden
stockades, wearing rusty Roman armour and riding ponies, then they
would have been a pretty scruffy bunch.

Mallory (1404-1471) cooked up the tale while in prison.

Of course, the myths are actually French, which is not so peculiar as
Britain was taken over by the (sort of) French Normans.

So Arthur could have been in France.
If so one would expect a shred of evidence.

I quite agree!  And don't worry about the story's being dressed up
with chivalry, etc.  Mideaval art assumed that people in the Middle
East in Jesus's time were dressed in the style current when the
painting, tapestries and stained glass windows were made.

Here is one site to spend the day with:  http://www.mystical-www.co.uk/king_arthur/

And there are many more with the search:  "king arthur" fact

And besides, the Round Table is hanging on a wall in a building near
Winchester Cathedral.  It looks just like the one in the movies, so
you know it is the original .... ;)

"Historical basis for King Arthur":

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