Mare Island Naval Shipyard, Defense Electronics Equipment Operating Center, I Street, terminus west of Cedar Avenue, Vallejo, Solano County, CA

Significance: Building 505 is a contributing element of the Mare Island Historic District. Building 505 is significant for its association with the communications facility at Mare Island, one of many non-shipyard missions that accrued to the base over the years, and is a rare example of an Art Deco or Moderne influenced building at Mare Island.
Survey number: HABS CA-1543-AJ
National Register of Historic Places NRIS Number: 75002103