Photogrammetry is the science of making measurements from photographs, especially for recovering the exact positions of surface points. We use stereo photogrammetry using latest high-resolution aerial imagery to capture our 3D Models. To explain complicated process in very few words, as a survey aeroplane flies over a city area, it takes series of photographs which overlap by 60%. With each photograph its GPS position, height, tilt, pitch and roll are recorded. Using this data + camera calibration data (to eliminate lens distortion effects), the imagery is triangulated to its correct real-world coordinates.