1. A method for associating geographic information with textual information, the method comprising: receiving, from a first computer, a request for a digital map of a specified geographic region; identifying a spatial key associated with the geographic region; encrypting the identified spatial key; embedding the encrypted spatial key into the requested digital map; returning, to the first computer, the requested digital map including the embedded encrypted spatial key; receiving, from a second computer, a request to decrypt the encrypted spatial key, the encrypted spatial key extracted by the second computer from the digital map; decrypting the spatial key; and returning, to the second computer, the decrypted spatial key.
2. The method of claim 1 further comprising embedding a bounding box in the digital map.