Washington County was among the earliest formed in Nebraska, having been established in 1854. Desoto and Fort Calhoun were the first county seats but in 1869 it was assigned to Blair. A 40x40-foot square brick building that had been designed as a school was first used. Twenty years later, amidst controversy over the need for a new courthouse the vote was 126 to 874 in favor of floating a $35,000 bond issue for the new construction.

Work began in 1889 under the direction of architect O.H. Placey and a Romanesque Revival-style design was selected. The builder was Richards and Company. They constructed the footings and foundations of limestone and the walls were laid up of St. Louis pressed brick with trim of Warrensburg Stone. There was considerable controversy during the construction. Some of the work was rejected and replaced and the architect resigned. Finally in 1891 the work was completed.

Numerous face lifts and improvements were made to the building beginning in 1936 with a $10,000 renovation by the WPA. The Treasurer's office, the court room and the 3rd floor all have been remodeled.

In 1995 a new addition and a complete renovation of the old building was dedicated.

The original High School in Blair dates back to 1869 when it occupied a hardware store at Grant and Walker Ave (now 16th & Grant). After additional buildings were erected in 1871 and 1872, a new high school was constructed in 1899. The building was designed by master architect, John Latenser, in the Richardsonian Romanesque style. It was built for about $40,000. The H-plan of the building was constructed over a raised brick basement giving the building 3 stories of useful space.

A large assembly hall on the third floor required a roof span of 60 ft and a ceiling which was finished in pressed metal including an ornate cornice. The brick used was a very hard burned red brick with thin mortar joints and a red sandstone trim. The corner stone was laid September 22, 1899 and the brick walls were completed later in November.

In 1929, a new modern building was built just north of the 1899 high school which required the removal of the old grade school in that location.

The building is in the Colonial Revival style and includes a large auditorium with stage.

Located on what was known as "Silk Stocking Row" in Blair during the late nineteenth and early twentieth centuries, the Abraham Castetter house is a product of Eclecticism. The original house was built in the French Second Empire style prior to 1876, with later additions following various architectural styles that were popular during the 1880s and 1890s. Castetter arrived in Blair in 1869, the year Blair was founded, and served as a banker and realtor in the original sale of new properties in Blair. In 1898 he established "The Banking House of A. Castetter." In 1887 Castetter deeded land to the city which formed the nucleus of the city park.

Over the years the Castetter house has seen many changes, a tradition which continues to this day. The six column front porch was an addition, the main entrance shifted from the East to the North side. At least two of the four bow windows are additions. It is believed that the larger bow on the west side was added in 1876. Inside are additional columns, a back stair way and an elevator. The House is heated by its original hot water system. Central air was added at the turn of the century.

The two story Carriage house contains its original horse stalls, and was believed to have been a horse collar factory in its past.

The Congregational Church of Blair is a good example of the Carpenter Gothic style of architecture. The board and batten structure was constructed in 1874 by George Sutherland, a local builder. The design was done by Charles F. Driscoll, an Omaha architect. The church had been organized on February 19, 1870 and by November 22, 1874 the new building had been completed and dedicated. The sanctuary was 28 x 40 feet built with a high peaked ceiling supported by heavy wood arches. The original building was placed on a very low foundation which did not include a basement. The south annex was added in 1884. Early pictures show the building and south annex on the original foundation served by dirt streets. Since Walker Avenue was paved with brick in 1921, this helps us to date additions to the building.

Another interesting bit of evidence shows up in the church minutes of September 1908 where an expenditure of $1241.25 is recorded for extensive improvements to the church which included a complete basement.

In 1957, an addition of Sunday School rooms was added to the west side of the building, matching the original building. In 1999 another addition was completed including an elevator and a new restroom.