The design of this Greek Revival former post office adheres to supervising architect James Knox Taylor's proclamation in 1901 that government buildings should return to the “classic style of architecture.” The Market Street elevation, clad in Pennsylvania white marble with a terra-cotta cornice, has a portico of eight fluted Doric columns, while the triglyphs and metopes of the full-facade entablature are appropriate to the Doric order. The post office occupied this building until 1937, when it moved to the larger Boxler Station (CA17). Between 1938 and 1968, the building housed a variety of government offices, including the Works Progress Administration, Internal Revenue Service, and Bureau of Mines. In 1968, Crown Construction (later Crown American Corporation; CA20) purchased the building and occupied it until 1989. Company architect Carl Barefoot renovated it by converting the mezzanine into a full second floor. Today, the building houses various offices.