Here's why:
* USF's Campus Layout: USF's main campus is spread out and includes various streets and buildings named with numbers.
* Common References: Students and staff at USF often refer to locations on campus by their street names, making "13th Street" a familiar term.
To be sure, you can:
* Ask someone at USF: If you are at USF, ask a student or staff member if they know what "13s" refers to.
* Check a campus map: Look for a street labeled "13th Street" on the official USF campus map.
Without more context, it's difficult to be completely sure, but this is the most likely interpretation.