Where Online Maps Meet The Road

In an age where satellite images are available at the click of a mouse, most people may not realize that people still go out and verify and add to satellite data. The San Diego Union Tribune has article on how cartographers at Navteq, Inc. flush out the little details in their digital maps. While everyone seems to have their preference among the various online mapping services, most people don't realize that the underlying data for all of them come from either Navteq or Tele Atlas NV.

The map makers cruise the streets in a small SUV. The vehicle is equipped with a Global Positioning System (GPS) antenna. In the back is a the GPS receiver unit, and a portable power supply. The receiver connects to a video recorder which captures road signs. Up front sits an observer who makes notes of new features on a pen tablet.

The data is later fed into Navteq's computer and included in the quarterly updates it sends to its customers. Each mapping service uses the data to generate its own driving directions which is why two different services may suggest different routes to the same destination. Navteq currently has 514 field analysts driving the streets and highways of North America and Europe to try and keep their maps up to date.