Richardson built the Allegheny County Courthouse and Jail in 1884–1886. Rough-hewn granite, heavy semicircular arches over the windows, steep roofs with dormers and turrets. Later this whole set of features would be named after the architect: the Richardsonian Romanesque style.
The buildings are connected by a small stone bridge over Ross Street, a single wide arch with windows along the top. The HABS documentation singles out the jail as an example of functionalism. In the photographs there are already high-rises all around, bulbous sedans drive along the street, and above the main entrance is still the same enormous arch in the rusticated wall.
