Embodiments relate to generating and using a directed graph as an advertising network taxonomy. Individual delivery locations provided by publishers for presenting advertisements are identified. A directed graph is generated that includes specific advertising opportunities that each correspond with an individual delivery location. The directed graph also includes multiple general advertising opportunities that correspond with aggregations of delivery locations. Multiple aggregations may each include all or part of the same set of delivery locations. Advertisers may then use the directed graph to purchase advertising opportunities, and advertisements may be served to delivery locations based on the advertiser selections.