I was surprised too, Oshyan

When I first saw the huge windows in the first movie I thought they were just a kind of big panorama windows and liked them. That was at VHS video times so I never had any doubt for a long time.
Just a graphical overview I found in the web. Here it's described as a botanical garden.
https://images.alphacoders.com/275/thumb-1920-275133.jpgI just added the link - hope it works.
Also I don't remember any film with a scene there. Only later in TNG and DS9 some scenes used a kind of arboretum or botanical garden.
I found out this detail when I examined the model but just these days I decided to work out illumination and textures for the close up.
There are unbelievable details in the model... I love it more and more!
Otakar, I want to be 40 years younger now! Immedately! Then I would buy that thingy!
(Perhaps I'll do anyway

)