1. A method of localising a vehicle hosting a sensor comprising the steps of: a) capturing data from the sensor providing a sensed scene around the vehicle at a current time; b) processing the sensed scene to extract a set of features from the sensed scene and to determine, using the extracted features, a position of the vehicle from the sensed scene in relation to the position of the sensor at an earlier time; c) comparing the extracted set of features from the sensed scene to one or more stored experiences, wherein each stored experience comprises a plurality of sets of features, where each set of features has been determined from a previously sensed scene, to ascertain whether the sensed scene can be recognised within any of the stored experiences; and d) if the extracted set of features of the sensed scene are recognised within any one of the stored experiences then that stored experience is used to produce an estimate of the position of the vehicle at the current time with respect to the stored experience.