This translates to "From what city are you?" in French.
Here's a breakdown of the sentence:
* De: From
* quelle: what
* ville: city
* êtes-vous: are you (formal)
For a more informal setting, you can use:
* D'où êtes-vous? (Where are you from?)
Example:
* De quelle ville êtes-vous?
* Je suis de Paris. (I am from Paris.)