Built in 1876 at the height of the quicksilver mining boom, the Lower Lake stone jail answered rapid town growth and an urgent need for civil order. Stephen Nicolai, one of Lower Lake's first stone masons, built it from local materials with the help of Theodore and John Copsey. The jail is one of the smallest in the United States. Theodore and John Copsey celebrated its completion so exuberantly that they became its first occupants, and rumor held that they were also the first escapees because they had failed to bolt down the roof.