1. It’s set in the future. There are two lines in the story that reveal this. At one point, it said that the lights were controlled with the flick of a switch (something like that). I don’t have my book in front of me but I will reveal page numbers shortly.
Also, Lia says that it’s odd that a prince didn’t have running water.
It is clear that there was a war and a nuclear bomb caused the destruction. It’s in one of the holy texts and I’ll add the page on a later date.
2. It’s set in America. In the opening chapter, Lia is looking at the Golden Gate Bridge so she lives in San Francisco.
Teravin is Avila Beach, CA
The ruined city Lia and Kaden travel to is Vegas. The fountain she bathes in is the Bellagio fountain.
Venda is Washington DC
Clues were the bison which are found in North America.
I’m sure there are other clues during her journey, but I haven’t figured it out yet.