Ammi B. Young, this building’s architect, was the first Supervising Architect (1852-62) of the United States Department of the Treasury and, as such, designed many of the nation’s federal buildings erected during those years from Maine to Texas. Most were, like this, inspired by Italian Renaissance buildings of the sixteenth century. It originally housed the main post office, the custom house, and the federal court. Located on what was originally Long Wharf Street, at the head of Port of Providence’s largest wharf, this monumental granite building was equipped with interior cast-iron shutters to render it impregnable under siege.  Massive amounts of structural cast iron, used here in a more limited way, had been introduced into the additions to the U.S. Capitol built between 1851 and 1855, just before this building went up. The large dome on top seems like an afterthought, which indeed it was, conceived after the main block of the building was designed. It lends the building great presence, however, and did so even more when the building was not surrounded by tall neighbors.

– 2003 Guide to Providence Architecture