The former site of the Fort Dodge Post Office and later the Federal Building first held a post office constructed in 1896, a Richardsonian Romanesque-style building with towers and heavy rounded arches. As the city outgrew that post office, it was replaced in 1908 by a neo-classical style building with rounded arched windows and columns. The second building was demolished around 1964 when the new Federal Building was completed two blocks to the south.