The cornerstone of the Trego County Courthouse was laid in 1888, and the building was finished in 1889 in the City Square in WaKeeney. It was constructed from Trego County hard stone and finished with Manhattan stone because they could not find enough of the hard stone. The building was designed in the American Queen Anne Style and featured an Elizabethan frontage. The highest cupola reached 100 feet in the air and the original tin roof was imported from Europe.
In 1951-52 the original roof was removed to make it a "modern-looking" building. The roof was also in disrepair, and this was the method chosen to repair it. Several scenes from the movie 'Paper Moon' were filmed in the courthouse in 1974. Then in 2012, the peaked roof was restored minus the cupolas but it closely resembles the original building. The original capstone was located and donated back to the county and it is once again back in its rightful place.
The interior has been updated but many of the historical features have been preserved.
Since the interior remains basically unchanged, it is one of the oldest Kansas courthouses still in operation today.
The historic Trego County Jail, in the basement of the Courthouse, was built at the same time as the rest of the building. It was used almost 90 years until 1976 when it was condemned. The Jail was pre-made elsewhere and shipped in. The historic jail cells were purchased from Pauly Jail Cells in St. Louis, MO for the complete sum of $2570. The unique jail cells feature flat bars rather than round ones and an usual locking system. Part of the jail remains intact today and is used for storage. Many other offices have come and gone from the Courthouse over the past century.