You can use the Location setting to target or exclude specific cities, regions and countries. We call this geotargeting.
Geotargets are set when initially launching a campaign. When prompted, simply type in the desired location that you wish to geotarget, and then click on that location in the pop-up menu that appears.
Adding geo-targets to your campaign
How to search for geotargets
When searching for the location that you wish you geotarget, enter only the name of the location and not additional parameters to narrow down results.
For example, if searching for San Francisco (city)
"San Francisco, CA" or "San Francisco, USA"
Results correlating to the name specified will appear, organized by Countries, Regions, Metros, and Cities. Simply search the list for your desired location and click "Done" to apply.