USPO Terminal Annex

The United States Post Office – Los Angeles Terminal Annex, also known simply as Terminal Annex, located at 900 North Alameda Street in Los Angeles, California, was the central mail processing facility for Los Angeles, from 1940 to 1989.

Across Cesar Chavez Avenue from Union Station, the Mission Revival and Spanish Colonial Revival building of Terminal Annex, which was designed by Gilbert Stanley Underwood, was added to the National Register of Historic Places in 1985.

Source: Wikipedia