The Cast-Iron Excelsior Block on East Wisconsin Avenue

The Iron Block Building, formerly known as the Excelsior Block, stands as the only surviving building in Milwaukee with a cast iron skin. Financed by James Baynard Martin, who moved from Maryland to Milwaukee in 1845 to deal in grain and real estate and later served as an insurance executive and banker, this five-story commercial structure was built in 1860. The cast-iron panels, a common technique from 1850 to 1870, were designed by George H. Johnson and cast by Daniel D. Badger's Architectural Iron Works of New York.

Initially named the Excelsior Block, this building features a captivating Italianate façade with round arches and iron surfaces deliberately grooved to look like blocks joined with mortar. The street-level entrance suggests a Roman temple, with its own pediment and entablature resting on pairs of Corinthian columns. While the building originally had four stories, it now stands as a five-story structure with a brick addition added to the south side around 1900.

Over the years, the street-level storefronts have been modified, but the upper stories are largely intact, except that the cornice was cut back and some iron removed. After undergoing a significant restoration in 1984, the Iron Block Building remains a notable example of early commercial architecture and the work of George H. Johnson, the English-born builder-architect who figured significantly in the development of building technology.

Sources: Wikipedia, OpenStreetMap, Wikidata, Wikimedia Commons