The interior of the library was destroyed, supposedly by an earthquake in 262 A.D, and the façade by another earthquake in the tenth or eleventh century A.D. It lay in ruins for centuries, until the façade was re-erected (anastylosis) by archaeologists between 1970 and 1978.
Celsus, in the honour of whom the library was originally built, had been consul in 92 AD, governor of Asia in 105 AD, and a wealthy and popular local citizen. He was a native of nearby Sardis and amongst the earliest men of purely Greek origin to become a consul in the Roman Empire and is honoured both as a Greek and a Roman on the library itself. Celsus paid for the construction of the library with his own personal wealth. Construction on the library began in 117 AD and was completed in 120, in Ephesus, a territory that was traditionally Greek. The building is important as one of the few remaining examples of an ancient Roman-influenced library. It also shows that public libraries were built not only in Rome itself but throughout the Roman Empire.
The interior of the library and all its books were destroyed by fire in the devastating earthquake that struck the city in 262 A.D. Only the façade survived. About 400 AD, the library was transformed into a Nymphaeum. The façade was completely destroyed by a later earthquake, probably in the eleventh or tenth century.
A marble statue of Celsus, which stood in the central niche of the upper storey of the Celsus Library. It is now in the Istanbul Archaeological Museum
Between 1970 and 1978, a reconstruction campaign was led by the German archaeologist Volker Michael Strocka. Strocka analysed the fragments that had been excavated by Austrian archaeologists between 1903 and 1904. In the meantime, some architectural elements had been acquired by museums in Vienna and Istanbul. In the process of anastylosis, those absent fragments had to be replaced by copies or left missing. Only the façade was rebuilt, the rest of the building remaining in ruin.
The edifice is a single hall that faces east toward the morning sun, as Vitruvius advised, to benefit early risers. The library is built on a platform with nine steps the full width of the building leading up to three front entrances. The central entrance is larger than the two flanking ones, and all are adorned with windows above. Flanking the entrances are four pairs of Composite columns elevated on pedestals. A set of Corinthian columns stands directly above the first set, adding to the height of the building. The pairs of columns on the second level frame the windows as the columns on the first level frame the doors, and also create niches that would have housed statues. It is thought there may have been a third set of columns, but today there are only two registers of columns. This type of façade with inset frames and niches for statues is similar to that found in ancient Greek theatres (the stage building behind the orchestra, or skene) and is thus characterised as "scenographic".
The main entrance is both a crypt containing Celsus's sarcophagus and a sepulchral monument to him. It was unusual to be buried within a library or even within city limits, so this was a special honour for Celsus.
Arete, (personification of virtue) in the Celsus Library
The building's other sides are architecturally irrelevant as the library was flanked by buildings. The interior of the building, not fully restored, was a single rectangular room (measuring 17x11 m) with a central apse framed by a large arch at the far wall. A statue of Celsus or of Athena, goddess of truth, stood in the apse, and Celsus' tomb lay directly below in a vaulted chamber. Along the other three sides were rectangular recesses that held cupboards and shelves for the 12,000 scrolls. Celsus was said to have left a legacy of 25,000 denarii to pay for the library's reading material.
The second and third levels could be reached via a set of stairs built into the walls to add support to the building and had similar niches for scrolls. The ceiling was flat, and there may have been a central square oculus to provide more light.
The style of the library, with its ornate, balanced, well-planned façade, reflects the Greek influence on Roman architecture. The building materials, brick, concrete, and mortared rubble, signify the new materials that came into use in the Roman Empire around the 2nd century AD.
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