A Cryptic Clue

[patriciamason]

This is the last clue on a cryptic quizI am doing.The answer is a place name in the UK(A town or a city)
The only clue I have is "AFamous Oil Painting"
Sorry,no idea how many letters or anything else.

A sample of the clues with an answer in the same quiz is:
Clue "Dick the detective is stupid.
Answer is Dumbarton.

It's alongshot but maybe,just maybe one of our members may be able to help if anyone is a cryptic quiz wizard.
If you can help I will be so grateful as at least 3 people are tearing their hair out over this one.
Thanks.

[scorpiojo]

Gainsborough??

[scorpiojo]

No, scrap that

[patriciamason]

scorpiojo that has been our first thought but we think the clue is too straight forward for that - not cryptic.Thanks for giving it ago though.Appreciated.

[mallyh]

im sure theres a place that sounds like old master but can't find it yet

[patriciamason]

rush - just grateful someone is trying.It's driving us mad.

[mallyh]

waterloo?

[mallyh]

waterloo liverpool?

[patriciamason]

Can you explain how you get to waterloo as I might be being abit thick about this but I can't see it?
Thanks .

[mallyh]

theres a famous oil painting of the battle of waterloo.

[Calibax]

Mona? (Anglesey)

[patriciamason]

Thanks to everyone who has helped.I didn't know there was aplace called Mona so I'm thinking that might be the best answer but I can see the others look good so will discuss with the lady who is doing the quiz.
Thanks so much - really appreciated.

[shoota]

Aldermaston - sounds (vaguely) like 'Old Master'

[patriciamason]

It is actually an anagram of An Old master so I'm now thinking this could be the answer we are looking for so thanks so much.I will go discuss this one with the lady who is doing the competition and which has been doing our heads in.Thanks to everybody who has been so helpful.This was the last clue to be solved.