Junction was platted on the plain of the intersection of the North and South Llano Rivers, hence its name, and was designated the county seat in 1876. This two-story, symmetrical Moderne composition of brick and stone, the third courthouse for Kimble County, was the penultimate of the twelve courthouses designed by Phelps of San Antonio. The courthouse’s facade is marked by six stone pilasters and with angular projections in place of capitals that create strong shadows on the otherwise flat facade. The central bay, which projects very slightly, is capped by a panel featuring a stylized eagle and bundled arrows. Although the courthouse was built before the New Deal and PWA funding, Phelps rejected the Beaux-Arts classical model of his earlier courthouses in favor of this austere, modern design.
At the corner of College and 6th streets and facing the square is the Old Rock Store building of 1879. A block north of the square, at 5th and Pecan streets, is the former county jail, a two-story structure of rough limestone blocks built in 1892.