The DB4GeO/DB3D Kernel is a completely in Java written library of 3D geometric data types (and its methods) and it even provides the possibility to build topologically defined nets (for example triangle nets) as well as access to a fast spatial index on the geometry data. A predecessor of the API called GeoToolKit has been developed at the Collaborative Research Centre 350 at Bonn University. DB4GeO is now maintained by the Chair in Geoinformatics (Prof. Breunig) of the Karlsruhe Institute of Technology. All of the textual data is coded in UTF-8.