A 3D representation of a geographical area is known as a topographic map or terrain model. Topographic maps utilize contour lines to depict elevation changes, illustrating the terrain's shape and features, such as mountains, valleys, and bodies of water. These maps provide valuable information for various fields, including hiking, urban planning, and environmental studies. 3D models of geographical areas can also be created using computer graphics or physical models to visualize landscapes better. This representation aids in understanding spatial relationships, planning construction projects, and assessing ecological environments for conservation efforts.