A three-dimensional (3D) volumetric geo-spatial querying system. The system can include a 3D GIS. The 3D GIS can include a database of geo-spatial data configured to store geo-spatial data using, not two-dimensional, but three-dimensional coordinates. The GIS further can include at least one database operation configured to process a database query against geo-spatial data stored in the database. Notably, the database operation can accept three-dimensional coordinates as part of the database query. Importantly, the 3D GIS can include a geo-spatial data encoder configured to encode the geo-spatial data prior to storing the geo-spatial data in the database. In particular, in one aspect of the present invention, the encoder can be a helical hyperspatial code encoder, or an oct-tree encoder.