Interoperable, standardised and adequate tools are important for coastal zone management and maritime safety. In respect to geographic data, it is a fundamental problem that data on the landward side is collected and main-tained by topographic mapping or cadastral agencies utilised primarily for development, nature conservation etc., while sea data is collected by hydrographical survey services, focusing primarily on marine navigation issues. Furthermore, the collaboration between member states at national, regional and local level can be improved. The BLAST project has a primary focus on “Bringing land and sea together”, by harmonizing and integrating data for land and sea. BLAST will in part improve the functionalities of databases, and it will provide input to improve SafeSeaNet. The overall aim of the project is to improve Integrated Coastal Zone Management and Planning (ICZM&P) and maritime safety in a broad sense, by improving and contributing to harmonising terrestrial and sea geographical data and by developing planning and visualisation tools as well as improvement of navigation, in the context of climate change. Achievements: • A prototype marine horizontal reference base in a consistent system for the North Sea area• Modern laser survey, combined with data provided by airbornjoint sea - land datasets• Report on current capability of GIS and tools for convertion• A prototype land-sea interoperable reference base for the case study areas and tested by practitioners• Documentation and methodologies to support the creation and maintenance of Inspire compliant land-sea in-teroperable reference base for Spatial Data Infrastructure (SDI)• A new methodology for chart datum realization based on the assimilation of data in a shallow-water hydrodynamic model• High-resolution digital models of the Mean Sea Level (MSL), the geoid and Lowest Astronomical Tide (LAT) for the North Sea area, which are consistent with the hydrodynamic constraints• Transformation parameters to link these surfaces to the national vertical reference systems around the North Sea; • A properly referenced and calibrated hydrodynamic model.• Online demonstration and report on an improved Digital Mariners' Routing Guide for selected North Sea ports.• A basic platform for further development and specifications for SafeSeaNet• Develop an automated tool for ENC harmonisationDevelop a conceptual model for integrated coastal zone planning in a context of climate change• A web site with information about and dynamic visualisations of future sea level rise and flooding• A set of strategies based on identified best practices for adaptation to climate change, and experience from tesing in municipalities.• A catalogue of mitigation strategies with emphasis on renewable energy and appropriate loactions for new plants• A web based information, indicator and decision support system for coastal zone planners and managers and erosion. A web based decision support system for ICZM in transnational context