M4/M5 corridors are probably good places to be looking.

Had a quick look at Reading, their largest room (The Palmer Building) has a capacity of only 400 which is I think too small to hold the biggest meeting (500 required I believe)

http://www.fmd.reading.ac.uk/Events_and_catering/Conferences/Conference_facilities.aspx

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James Hardy
(id:MrWeeble)