The document describes a Geographic Knowledge Base (GKB) that was created to integrate geographic and network knowledge from different sources and represent it as ontologies. The GKB combines hierarchies of geographic features from various sources using an algorithm to identify common instances and merge the hierarchies. Rules are then used to assign geographic scopes to websites based on matching their domain names to feature names in the GKB. Applications that have used the GKB include named entity recognition of geographical references and assigning documents to geographical scopes for information retrieval.