The post office in Rugby was the last of nine post offices in the state built between 1932 and 1940 with standardized plans. The Moderne building’s exterior walls are tan brick with limestone sills, and the hipped copper roof has a tall square metal cupola. Above the front entrance is an eagle motif in a circular background of satin aluminum. Kenneth Callahan painted the interior mural, Rugby, the Geographical Center of North America, in 1942, funded by the New Deal’s Fine Arts Section. Depicting Rugby’s claim to be the geographical center of North America, the mural is a sketchy map of the continent with Rugby at the center flanked on the left by a tall figure holding a shock of wheat and on the right by a man standing next to a cow.