You can use the Location feature within your audience to target or exclude specific cities, regions and countries. This is called geotargeting.
Create geotargets when you create a campaign. When prompted, enter your desired location and then click on that location in the dropdown menu.
Add Geotargets to Your Campaign
Navigate to your Ad Campaigns tab.
Hover over the campaign you want to edit and click the circle icon with the ellipses.
Under the Audience section, enter a location to either Target or Exclude.
Search for Geotargets
When searching for a location, 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. Search for your desired location and click Done to apply.