mechaerik
Tuturuu!
That's an Arcology.
It's in the Next War mod.
I think you mean to the left.
You know, there's an even more advanced people (check the evidencie in the following link: http://forums.civfanatics.com/showpost.php?p=8165742&postcount=700 ). They ALL achieved the same as your town, & they weren't even fully civilized!!The secret to flight has been discovered in a tiny coastal town.