The Historic Microsoft Headquarters are located in Albuquerque, New Mexico. Microsoft Inc. was founded here and remained in Albuquerque from 1975 to 1979 before moving to Seattle.

The plaque on the rock (Streetview) reads:
Microsoft Inc., housed at this site from 1975 to 1979, was founded here by Paul G. Allen and Bill Gates, whose passion for technology and vision of "a computer on every desk and in every home" led to the development of Microsoft's groundbreaking software. Paul Allen and Bill Gates would like to acknowledge the important role that the city of Albuquerque played in the company's early development, offering an environment that stimulated creativity and encouraged entreprenurial spirit.

channel9.msdn.com/series/history

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