Typewritten on the reverse: "One of the First Buildings in Sparta.
Erected in the Fall of 1851 by R.J. Castleman on the West border of Beaver Creek between Main and Oak Streets, and first occupied by him as a residence and hotel.
In the winter of 1851-2 Rev. Frederick Walrath held the first Church Services here.
In the spring of 1852 the first Post office was established in one corner of the building. Wm. Petit was the first Postmaster and Mr. Castleman was his deputy and the mail was received once a week from La Crosse.
In the Fall of 1852 G.H. Ledyard opened the first store in the front room.
Dr. G.W. Millegan, the first Doctor in Sparta lived here for several years.
In later years the building served as a lumber warehouse for Andrew Thorbus, Manufacturer of Wagons, who was succeeded in business by his sons. Martin and T.O. Thorbus, who continued to use the building until it was demolished about 1900."