Apparently, the Hanging Gardens might not have been in Babylon at all, but further north. Archimedean screws would have been used to deliver the water to the different levels. These perhaps could be added?
Quoting Hildigrim Took
Not even joking this is what I was going to build... -_- Awesome job though! :) Isn't there Btw supposed to be a reference pic? Just a heads up :)
Probably one of the most popular wonder that fits the category, I would be surprised if it was a popular choice. As for the reference, there isn't a definitive image for it, I made my own version based on various pictures I've seen.