20. The system of claim 15 , wherein the second computer comprises a search engine, wherein the search engine indexes the spatial key with content associated with the digital map, and wherein the search engine performs location based searches using the spatial key.
15. A system for associating geographic information with textual information, comprising: a processor, and a non-transitory computer-readable medium including instructions configured to cause the processor to carry out the steps of: 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 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.