Google Maps is cool and very helpful, but still very limited. 3D city models are slowly being generated by crowd-sourced designers but take lots of time to develop.

C3 Technologies‘ method not only is more¬†accurate, but also much faster. They take multiple passes of aerial photos with DSLRs and using a special computer system, stitch the photos together to create the models and textures. The system is relatively automated and accurate down to 6 inches.

The technology was originally used for missile-targeting systems but now has been adapted for 3D mapping.