If you really want to qualify as a member of the Geek Tribe, you have to make a pilgrimage to the holy land. Fortunately with high tech, there's not just one sacred site but dozens, says John Graham-Cumming, author of "The Geek Atlas," a guide to "128 Places Where Science & Technology Come Alive."

Graham-Cumming's guide book covers everything from where Newton's apple fell to the pub where Watson and Crick announced they'd unlocked the secret to DNA. He also has a handful of entries specific to computers.

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"If you're a computer person, the three essential places to visit are the Computer History Museum in San Jose, Bletchley Park, and the London Museum of Science," says Graham-Cumming. "At the latter you can see a working model of Charles Babbage's Difference Engine, which they built using the tools available at the time. It's remarkable."

Those are hardly the only ones. We've identified the 12 most sacred places where IT enthusiasts can go to pay homage to the computing gods that passed before them -- or at least catch a peek at where some of the more exciting events in IT lore occurred. Fortunately, would-be pilgrims can do a lot of the traveling via the Web, saving wear and tear on the sandals and sackcloth.

Tech mecca No. 1: 367 Addison Ave., Palo Alto, Calif.

Tech mecca No. 2: 2066 Crist Dr., Los Altos, Calif.

Tech mecca No. 3: 232 Santa Margarita Ave., Menlo Park, Calif.

Tech mecca No. 4: CERN -- Geneva, Switzerland

Tech mecca No. 5: Bletchley Park, England

Tech mecca No. 6: Xerox PARC -- Palo Alto, Calif.

Tech mecca No. 7: Ames Lab, Iowa State University -- Ames, Iowa

Tech mecca No. 8: Moore School of Engineering, University of Pennsylvania -- Philadelphia

Tech mecca No. 9: IBM's "Main Plant" -- Poughkeepsie, N.Y.

Tech mecca No. 10: Room 2713, Dobie Hall, University of Texas -- Austin, Texas

Tech mecca No. 11: Kirkland House, Harvard University -- Cambridge, Mass.

Tech mecca No. 12: Lyman Residence Hall, Stanford University -- Stanford, Calif.