Aria the Animation follows Akari Mizunashi as she navigates her new life in Neo Venezia, a city on the terraformed planet Aqua that's modeled after Venice.
She works as a novice Undine, a gondola tour guide, at the Aria Company.
The anime focuses on Akari's journey as she explores the city, interacts with other Undine and residents, and learns about the beauty and wonder of Neo Venezia and life itself.
It's a slice-of-life story about her experiences and the lessons she learns as she works towards becoming a full-fledged Undine.