The invention relates to a system for verifying geographical descriptiveness of a media file, such as a picture. The system comprises storage means adapted to store a media file, communication means adapted to send said media file to a plurality of user terminals, and to receive, from the user terminals, data indicating a guessed geographical position with which the user of each user terminal associates the media file. The system also comprises calculation means adapted to determine whether the media file is indicative of a geographical position based on the guessed geographical positions received from the plurality of user terminal.