I have a feeling that fantasy has become enormously much bigger of late. This is particularly obvious to me in fantasy art and concept art. Here, oversized structures aren't as "natural" as in sci-fi, where we're dealing with planet-sized things; and I accept that concept art exaggerates to get an idea across. I do enjoy enormous buildings and creatures. Still, sometimes it seems that artists, including authors, only know one way to make things more interesting - scale it up.
When I am coming up with concepts for my world Genius Loci, I wonder how to point out that something is big without making it ridiculously large. Mankind has built some impressive structures in its time; as a worldbuilder I'm perfectly happy with the size of Rome's Circus Maximus, Teotihuacan's sun pyramid, or Notre-Dame-de-Paris, that all leave us with a feeling of grandure; but if I compare a structure to them, does the audience know I mean "really, really big"?
How do you feel about size in fantastical worlds? Do "smaller" structures still impress you? What do you regard as big?

I'm using Patricia Anawalt's book "The Worldwide History of Dress" published by Thames&Hudson Ltd., the German edition was published by Haupt Verlag as "Weltgeschichte der Bekleidung". The book provides valuable anthropological insight, and fantastic photos instead of lithographs, showing the behaviour of the fabrics very well. It's especially useful for me because it shows original detail concerning accessoires (jewelry, body painting, belts, scarfs and whatnot).
I often hear Taschen books cited as great sources, but I must say that they often seem historically inaccurate (seeing as their lithographs and drawings were made in a time when people thought the Neanderthaler must be dumb, when he was in fact as smart as anyone else then).