GeoS 2005wasthe 1st InternationalConferenceon GeospatialSemantics. It was held in Mexico City, November 29 and 30, 2005. Within the domain of geographic information science (GIS), semantics has become one of the most prominent researchthemes over the last few years.Such concepts as ontology-driven geographic information systems and the geospatial Semantic Web have fuelled a plethora of researchin such areas as geo-ontologies andsemanticsimilarity.ThesetopicscomplementthetraditionalfocusinGIS- search, which has dealt primarily with geometric entities, their spatial relations, and e?cient data...