The Macoupin County Courthouse is Carlinville's signature landmark, a large Second Empire limestone building finished in 1870 at a staggering cost for a rural county. Its "Million Dollar Courthouse" nickname stuck because the price became a local scandal, with accusations of graft and overbuilding.
The building still dominates the square. Even if you only see the exterior, the scale is striking: dome, mansard roof, heavy masonry, and the confidence of a county seat that briefly imagined itself as something grander. Tours are sometimes available through local tourism contacts.