Despite the success in the application of ontologies as tools supporting semantic based approaches in various application areas, the lack of simple instruments for their visualization and editing still hinders their diffusion and wide adoption. This paper introduces NavEditOW, a system for the visualization, navigation, updating and maintenance of ontologies through the web. The paper describes the functionalities offered by the system, as well as its internal architecture. A description of its application to the representation and management of archaeological knowledge for the description of publications in an e-library ends the paper.