Meant to say this for a long time; I get confused when folk here talk about sections on the river. I've got used to EA's terms (bit of a chance as they seem to rename sections every time there is a management reshuffle /forums/images/graemlins/laugh.gif ).
To me "Upper Thames" is that lovely quiet bit above Osney where "Palazzi degli gin" cannot venture (easily), but I suppose for many Abingdon is the limit.
For consistency I'll accept EA's current definition:-
Upper Thames (Cricklade to Cleeve Lock)
Middle Thames (Cleeve Lock to Bray Lock)
Lower Thames (Bray Lock to Teddington Boundary)
'course that's shot to pieces as there are "Upper Thames" -
-Rowing Club at Henley,
-Yacht Club at Sonning.
Wouldn't surprise me as there seems to be a concerted effort to completely kill off leisure boating on the Thames and the whole country for that matter. You'll soon need a license to own a boat!