The concept of a "Digital City" does not refer to a single, specific city. Instead we pursue a functional approach with four interdependent aspects:

• Supporting data and information,
• providing a communication infrastructure,
• delivering value added information and innovative services, and
• using virtual environments in planning, decision-making and analysis.

In combination, these functional levels describe an important and emerging field as:

• more and more geo data are collected at high spatial and temporal resolution on an operational basis;
• the dynamic nature of data related to digital cities poses new challenges;
• these data are relatively easy to acquire and to a certain degree freely accessible;
• and, as a consequence, more and more people with various interests and levels of expertise are using these data as standard input for their needs.

However, due to the amount, complexity and heterogeneity of data, the underlying processes for exploring, analyzing and finally presenting new information and knowledge associated with the Digital City are in development and far from operational.

Approaches from geovisualization can make an important contribution, in general in developing, integrating and evaluating interactive maps and cartographic techniques that are designed specifically for visual exploration and analysis. Geovisualization has potential for a number of aspects of the Digital City, as listed on the right hand side.

Contributions are invited on these and related topics in which visualization is either used in an urban context or in way that may be adopted for use in the exploration, analysis and development of the Digital City. We encourage the submission of contributions that consist of video and software demonstrations, proposals and position papers as well as traditional academic papers.