The scrolls of the manuscripts were kept in cupboards in niches on the walls. There were double walls behind the bookcases to prevent the them from the extremes of temperature and humidity. The capacity of the library was more than 12,000 scrolls. It was the third richest library in ancient times after the Alexandra and Pergamum.
The facade of the library has two-stories, with Corinthian style columns on the ground floor and three entrances to the building. There is three windows openings in the upper story. They used an optical trick that the columns at the sides of the facade are shorter than those at the center, giving the illusion of the building being greater in size.
The statues in the niches of the columns today are the copies of the originals. The statues symbolize wisdom (Sophia), knowledge (Episteme), intelligence (Ennoia) and valor (Arete). These are the virtues of Celsus. The library was restored with the aid of the Austrian Archaeological Institute and the originals of the statues were taken to Ephesus Museum in Vienna in 1910.
There was an auditorium ,which was for lectures or presentations between the library and the Marble Road, was built during the reign of the Emperor Hadrian.