Industries that use DTM/DSM mapping are forestry, mining and land management. Digital Elevation modeling forms the basis for specialized applications used by these industries including volumetric calculations in the case of mining. The same way, DTMs are used for contour generation, which further increases detail level through contour lines for any elevation grid data set. Also, urban mapping applications use elevation models for highly-detailed 3D city models. These form the basis for digital twin models and smart city development.