I've been looking through old film magazines recently, particularly Sight and Sound published by The British Film Institute. On the back of almost every issue I have from the 1960's there is an advertisement for a film, sometimes two at The Academy Cinema, Oxford Street.
I've been intruged simply because I know the West End relatively well and I haven't ever, in my time in London seen a cinema on Oxford Street.
It turns out that The Academy was a very important cinema in it's day, probably the most important in London outside of The National Film Theatre. As this webpage shows The Academy was '...the first and most prestigious British art house cinema.' I'd been looking on the web for a couple a couple of weeks, trying to see what happened to this place which must have been glorious and to see specifically where it stood. Sadly, it was demolished, this article explains in more detail as well as some comments from those who actually visited it along with a great photo of the inside.
The Cinema Treasures website is well worth a browse, currently it has 441 listed for UK as well as amazingly cinemas from around the world.