A new approach to spatioterminological reasoning is presented which is based on a hybrid knowledge representation system architecture and on a representation of the RCC family tree in OWL. The knowledge base into which the family tree is imported holds role assertions in terms of RCC-8 relations between individual regions. It is a key component of a semantic layer constructed on top of an environmental database which aims at facilitating access to users by supporting a sophisticated while easy-to-use search engine. Issues of world assumption and spatial extension to OWL are discussed.