“Gaol” is an old British way of spelling jail, but you’re not likely to encounter it these days. One of the projects from mid-way in development of this process was a jail, connected with the second Fennimore County courthouse, as well as the Agincourt City Hall. At least that’s the way I remember if from circa 2008-2009.
Eric Hoffer (whose permission I haven’t asked) took this on as a “now” project, contemporary with his own effort — not necessarily an easier row to hoe.
I borrowed this image from a personal site he doesn’t seem to be using these days. But here’s the link to the page with other images of his jail. It doesn’t show much of the immediate context, though I can tell you it’s on the north side of the courthouse and (as I recollect) adjacent to the city hall. The would be about the northeast corner of Second Street N.W. and Agincourt Avenue.
If anyone knows Eric’s whereabouts, let me know.