One Shields Avenue, Davis, CA 95616 is the fictional address used for mail sent to UC Davis. As it can be difficult to address mail to the university and departments within, the university worked with the Post Office to create an address where mail could be sent without problem. It refers to Peter J. Shields Avenue. It sometimes appears as One Shields Way.
Most online maps geocode this to be at the corner of Shields Avenue and East Quad. It is uncertain as to whether this is an extrapolation of the Davis grid, or is intentionally coded to be at the location of Shields Library.
The fictional address was created in 1996 to honor Peter J. Shields, as well as save costs to the University and make mail delivery faster. (source: California Aggie). The Mail Division suggests that you format your mail to the University as follows:
Name of Department and Recipient University of California One Shields Avenue Davis, CA 95616-XXXX