A short climb of the impressive Renaissance double staircase takes one to the Reading Room, enclosed by stately columns of the Ionian Order, and topped with a glass ceiling. Several pieces of ironwork make for proper decoration for this otherwise austere site. The structure is often cited as a paradigmatic example of Neo-classicism. Erected in the period of 1887 – 1902, following the preliminary designs of Danish architect Theophile Hansen, the structure was finished off by star architect, Hernest Ziller, and he worked on the entrance and the staircase formation.

The entire project, however, is much older, as there is a decree of 1858 issued by King Otho that declares the need of a National Library for Greece. The country's first public library was founded on Aegina in 1829, and was only relocated to Athens in 1834. The construction of the present-day structure was triggered by then-Prime Minister Charilaos Trikoupis in the 1880s. The project was executed via fund-raising and large donations.