In the museum, on the wall behind the scale model of the castle, is a drawing of one of the statues of the legendary shachi sea creatures (half fish, half dragon), gazing down on the city from the roof. The drawing is actual size of the rooftop finial and you can see the 1/30 scale replica of that fish/dragon on top of the model. I love when people help make math realistic and relevant.
(You have to look very closely at the far end of the roofline of the gray model to find the shachi sea dragon that is 1/30th of the picture on the wall.)