The first original courthouse was constructed on the Blanco town square in 1860. The courthouse was later replaced in 1885 by a limestone structure that came to be known as the Old Blanco Courthouse after Johnson City became the county seat in 1890.

The Old Blanco Courthouse was built during 1885-1886 by Ernst Ruffini who dominated the design of county courthouses in Texas during his short career. Mr Ruffini designed eleven courthouses in nine years. The Blanco County courthouse is an example of his outstanding design work.

The courthouse has been used as a school, a bank, an office building housing lawyers, doctors, dentists, an opera house, and a hospital.

The Old Blanco Courthouse was for sale for a number of years. The building was sold in 1986 and the new owner's plans included dismantling the old courthouse and moving it to his ranch. This outraged the citizens of Blanco and the Old Blanco County Courthouse Preservation Society was formed drawing up a formal petition opposing the news owner's plan to remove the Old Blanco Courthouse from the square.

In August 1986, advocates of the Courthouse crowded into the City Council meeting determined that an Historical District ordinance would be passed to prevent the loss of the courthouse and additional buildings. A successful outcome preserved Blanco's rich history. In May 1998, the Old Blanco Courthouse was rededicated and reopened for use by then Governor George W. Bush.

The old Blanco County Courthouse is now open as a visitor center, gift shop and community center. It is located on the town square in Blanco at the intersection of Highway 281 and Highway 165.

North Elevation of the Blanco Courthouse (Picture courtesy of the Texas State Library & Archives Commission)

The plans originated with W.W. Larmour (of San Antonio) but were used without permission by the contractor J. H. Walker for the Tom Green County Courthouse - The supervising architect for the Tom Green County Courthouse was Oscar Ruffini who sent a copy of the plans and a photo of the courthouse to his brother Frederick Ernst Ruffini (of Austin) who in turn modified them for the Blanco County Courthouse and for contractor Captain James B. Smith who then used the Ruffini design for the Callahan County Courthouse and the Concho County Courthouse. - Oscar Ruffini then reused the F. E. Ruffini plans for the Mills and Sutton County Courthouses.