OCTAS visualizes 3D subsurface geologic model with simple and easy steps. It is possible to import models from other software, such as GEO-CRE. Moreover, it allows overlaying various ground information over the models, including specific geotechnical information and terrain data from a drone. OCTAS can create geotechnical cross-section at a free position and export it to CAD. To improve the quality of the model, various optional functions, such as visualization of measurement and physical data, are under development.