Ability to sort posts by category and location?

Hi,

I run a WordPress website in which i want to have the ability to arrange posts by category and location ( two levels of classification ) on the front end and the back end. Currently i can arrange by category. Thats pretty easy. But i also want to filter the posts further so that they are sorted by location as well ( lets say Place A and Place B ).

For categories, i just create a set of categories, select the categories while publishing a post and finally i let my website viewers to choose their category from a custom menu on a sidebar.

So can you guys recommend a plugin or tell me how to further classify the posts by locations as well?

Thanks alot!