Given to the university by the class of 2004, Historical Marker #2138 commemorates the Main Building. It opened in 1882 and was known as the Main or College Building. It is the only surviving building out of four original structures located here when UK was known as State College. It contained classrooms, offices, and a chapel for student assemblies. It was designed by architect H. P. McDonald and built of brick fashioned form campus clays and stone at a total cost of $81,000. On the roof of the building was 157 feet high cupola with a clock and "captain’s walk," used by the local Weather Observatory, but was removed in 1897.
A post office and bookstore opened in 1918 and a cafeteria in 1919, but both were removed and relocated by 1929. Interior renovations were completed in 1929, 1939-40, and 1964. By the spring of 1948, the building housed only administrative departments and was renamed the Administration Building. A fire on May 15, 2001, nearly destroyed the building, which led to extensive renovations. A fourth floor and two balconies were added and it reopened on October 25, 2004. It now houses administrative offices, the president's office, classrooms, conference rooms and the visitor's center.
The UK Senior Challenge Historical Marker Project, administered by the Kentucky Historical Society, began in 1994 as a way for the graduating senior class to leave a memorial to the university. Every year since then, the UK historical marker committee has decided on the topic, raised the money, and written the text for the markers.