The Customs-House in Barnstable on Cape Cod was new when Willliam Wall came up from New Bedford and painted it 1857.
You can see it, it's the red building just to the lower left of the enormous flag hanging over the road.
The National Park Service website says,
The U.S. Customshouse in Barnstable is architecturally and historically significant for its role in the maritime commerce of Cape Cod in the late 19th century. The Seventh United States Customs District was established in 1789 with the Town of Barnstable as its administrative center. Customs activities took place in the collector's home until the mid-19th century when collector Sylvanus B. Phinney secured congressional funding to erect a fireproof, brick and cast iron customshouse/post office in 1855. Ammi Burnham Young, Supervising Architect of the Treasury Department, designed the two-story, Renaissance Revival style building with an advanced cast-iron structural system by 1856.
The customshouse occupied the second level until 1913, while the first level served as a post office until 1958. The County Extension Service replaced the customhouse on the second level from 1924 to 1957. The Federal government deeded the building and grounds to the Town of Barnstable in 1960 for use as a historical museum...
The NPS web site has a couple of nice, more recent photos: U.S. Customshouse (Barnstable)
Here are some photos I took a couple of years ago. This is from the spot Wall stood when he painted. Most of the buildings are still there, you just can't see them for the trees. There are far more trees on the Cape now than there were in the 19th Century, but that's a story for another post on another blog:
A little closer:
Here's the architect's Wikipedia entry: Ammi B. Young. The Boston Custom House was his first customs house effort:
Entering the 1837 competition to design the Boston Custom House, Young submitted another cruciform scheme combining a Greek Doric portico with a Roman dome. Planned on a large scale at what was then the waterfront, the building reflected the strength and confidence of the young, growing nation. It won, defeating several other entries, including one by Asher Benjamin. Young was appointed supervisor of construction, which took from 1837 until 1847. In 1838, he established a Boston drafting room. The building's 32 columns were each carved from a single piece from Quincy granite. They measured 5 foot 4 inches in diameter, stood 32 feet high, and weighed 42 tons. Purists decried the Roman dome on a Greek form. Far less sympathetic to the building's Greek form, however, would be the soaring Custom House Tower which replaced the dome in 1913-1915. Boston's first skyscraper, it was designed by Peabody & Stearns to add both office space and presence to a building obscured by later others.
If the Wiki entry is correct, the Barnstable building was his first custom house design after his appointment as the first Supervising Architect of the Treasury in 1852. In this position (until 1862) Young
... produced designs and specifications for federal buildings ordered by the government to facilitate its various functions throughout the nation. Mandated to be fire-proof, the custom houses, post offices, courthouses and hospitals he built featured masonry foundations, walls and vaulting, with cast iron interior structural and decorative elements, including columns, stairways and railings. Heavy iron shutters were mounted on the inside of windows. Floors and treads were marble, and roofs were galvanized metal. Column capitols, fascia and pediments on the exterior, when not stone, were cast iron painted to look like stone -- which drew criticism of parsimony by the federal architect. Cast iron components were manufactured to Young's specifications in New York state, then shipped to building sites.
Sources: Wikipedia, National Park web site. A print of William Wall's painting is available from allposters.com, the source of the picture above.