To enable a future powered by augmented reality, autonomous vehicles and digital mapping we need a global high definition 3D map. This can only be achieved by utilizing the broad array of data sources imaging our world - camera phones, 360 video, drones, aerial, satellite, radar, LiDAR. To make all these imagery sources cooperate and align we need a common ground truth - what we call a ground control surface. Leveraging geomatics, computer vision and machine learning we generate a self improving ground truth and align multiple data sources.