- Cottonwood County Historical Society Mural - Windom MNThis mural "Agricultural Theme" was painted for the Windom post office by Charles W. Thwaites in 1943 with funding from the Treasury Section of Fine Arts. The mural, as well as two alternate sketches composed by Thwaites, now hang in the county museum.
- Post Office Mural - Chilton WIThe mural "Threshing Barley" was painted by Charles W. Thwaites in 1940. It was a winner of the Treasury Section's 48-State Post Office Mural Competition.
- Post Office Mural - Greenville MI"Lumbering" John Thwaites painted this oil on canvas mural in 1940 for the Treasury Section of Fine Arts. It is viewable in the Greenville post office lobby.
- Post Office Mural - Plymouth WITempera mural entitled "Making Cheese" painted by Charles W. Thwaites in 1942.