Consider the above. Is it a castle? A church? Perhaps a school? How was it built – was magic involved?
What would it be like for a person arriving for the first time?
What would it be like if the bridges collapsed/were destroyed? Is arrival by water even an option? Look at the small protruding cliff – is it possible to gain access that way? What sort of structure might be underneath all that water?
What would happen if someone wanted to find out? Why would they want to find out? What kind of person would want to find out?