Trust good old Suetonius…
Its vestibule was large enough to contain a colossal statue of the emperor a hundred and twenty feet high; and it was so extensive that it had a triple colonnade a mile long. There was a pond too, like a sea, surrounded with buildings to represent cities, besides tracts of country, varied by tilled fields, vineyards, pastures and woods, with great numbers of wild and domestic animals. In the rest of the house all parts were overlaid with gold and adorned with gems and mother-of-pearl. There were dining-rooms with fretted ceils of ivory, whose panels could turn and shower down flowers and were fitted with pipes for sprinkling the guests with perfumes. The main banquet hall was circular and constantly revolved day and night, like the heavens. He had baths supplied with sea water and sulphur water. When the edifice was finished in this style and he dedicated it, he deigned to say nothing more in the way of approval than that he was at last beginning to be housed like a human being.
Now turns (…) out the story about the revolving room was true.
More details here.