1. An apparatus for detecting an object around a vehicle comprising: a vehicle positioning device operable to detect a vehicle position; a database, the database including three-dimensional geographical data; an area defining device operable to utilize the three-dimensional geographical data to define an area for detecting a target; object detecting device operable to measure a distance between a vehicle position and an object and determine whether the object is within the area defined by the area defining unit; an output device operable to identify if the object detecting device has detected an object within the area, wherein the object detecting device compares the distance between the vehicle position and the object with the distance between the vehicle position and a building.