Nit necessarily steam trains.

BUGGER! Nit = not.

[Irouléguy] Built or constructed? SORT OF - but, then again, not in the way I think you mean
[Phil] Mineral metal? NO ... it could be but I wouldn't like to mislead you.
[Raak] Peak Oil? NO
[Rosie] Transport? NIET

[Raak] Bigger than a house? NO ... not normally, although it could be but I wouldn't like to mislead you :-)

[Raak] Ornamental? NO
[Graham III] Conceptual? Er ... NO
[Irouléguy] Artistic representation of some kind? NO

[Raak] Would you buy one of these? NO
[Rosie] Seen in town? YES
[CdM] Humanly constructeded? OH YES *audience applauses mainly because there's been precious little to get excited about so far in this game*
[Graham III] Would you want one of these? You might ... but you might not

add/ Talking of which, I'm wondering why the audience didn't hum and ha a bit when I answered Irouléguy's last question. They were obviously asleep. Apologs

[Graham III] Billboard advertising? NO

[Raak] A monument? NO

Hint: This is definitely ABSTRACT with MINERAL to help it on its way. The human connection means it's 'constructed' and used by humans rather than beasties.

[Quendalon] A congeries [a collection?] NO
[Raak] Fictional? NO
[Rosie] Some kind of open space? NO ... but there is a kind of connection with open space.

I consider them to be the same thing.

Scrap that -- if you can see it in a town, the answer is presumably yes.

[Red Wolf] Is it a square or a plaza? NOT IN THE WAY YOU MEAN ... but you are, quite possibly unwittingly, getting closer to the structure of this thing
[CdM] 5 sensage? I'm replying because the 'in a town' answer could equally have been an 'out-of-town' answer and it would be unfair to mislead you. The answer is, however, YES :-)

Second hint: Just look back at some of the questions you have all asked when presented with an ABSTRACT +.

[Rosie] Visually appealing? It could be , but not really relevant at this stage of the game