The first public library in Columbus, the downtown reading room on the first floor of City Hall, opened on March 4, 1873, and contained 1,500 books.

[3] Columbus was initially passed over by Carnegie for funds to build a large main library, as it was against his preference for smaller branches accessible to local working class residents.

[13] The renovation was finished on January 2, 1991, and dedicated on April 30, 1991, by First Lady Barbara Bush and Ohio governor George Voinovich.

[17][18] The 1991 addition was the focus of the renovation,[19] replacing the windowless east facade with two stories of windows overlooking Topiary Park.

The 1991 addition was constructed before the internet was popular, and before smartphones existed; thus the 1991 building was more-so built to house books.

It was built in a Beaux-Arts style (sometimes referred to as Second Renaissance Revival-style[9]), using white Vermont marble on a gray granite base.

[2] A smaller frieze over the central entranceway reads "Open to all" in bold capital letters (Carnegie required that anyone use the libraries he funded).

[20] The facade also features a row of benches, with the inscription "my treasures are within" across them; this phrase was suggested to be used by Carnegie, in his letter awarding his funds.

Friezes atop windows on the west facade mention the classical poets Virgil and Homer; other inscriptions credit Carnegie for funding the library and another has the Latin word "anno" followed by Roman numerals "MCMIV", meaning "the year 1904", when the cornerstone was laid.

[23] The interior of the Carnegie building has coffered ceilings and barrel vaults in its main corridors, along with dark green columns and pilasters, made with an imitation marble technique known as scagliola.

The Architectural Review praised its simple plan and elegant facades, writing "we can recollect no Renaissance building of its size more charming".

[21] The 1991 construction and 2015 renovations won the Columbus Landmarks Foundation's James B. Recchie Design Award; the latter project beat out the National Veterans Memorial and Museum and the Michael B. Coleman Government Center in 2019.

The first floor contains the Grand Atrium, the children's section, an auditorium, meeting rooms, a gallery, a gift shop, and Carnegie's Cafe.

[29] The park's central feature is a topiary garden, designed to depict figures from Georges Seurat's 1884 painting, A Sunday Afternoon on the Island of La Grande Jatte.

Services offered include wireless internet, public computers and tablets, and discovery boards (consoles that aid in navigating the library and learning about it).

[26][27] The library currently serves a portion of the city's homeless population, as the facility offers warmth, drinking fountains, bathrooms, computers, and homeless-specific resources.

[26] The organization also operates a biannual sale of about 18,000 books, graphic novels, CDs, and DVDs (materials from the library that are worn or not in demand) at the branch, which raises about $15,000 each occurrence.