How old is your sidewalk? Quite possibly more than a century old. The spelling “Pittsburg” was federally official between 1891 and 1911, and though some institutions continued to use the shorter form after the spelling officially reverted to “Pittsburgh,” the lettering on this bronze plaque is very much a nineteenth-century style. The Pittsburgh Orbit site featured this plaque a few years ago in its roundup of sidewalk plaques; the editor there is of the opinion that the sidewalk could not be more than a century old, but old Pa Pitt is of the opinion that well-laid concrete is forever. Especially if you repair the segments that crumble too much.