Tabularium

Built during the late Republican period, the Tabularium was a site used for the conservation of bronze tabulae, which contained laws and official deeds of the Roman state. It was originally completed by Quintus Lutatius Catulus, who was a consul in 78 CE, and this effort was a part of his program of public works that called for the redevelopment of the Capitoline Hill after a fire broke out in 83 BCE.

Architecturally, the first floor consisted of a pavilion-vaulted gallery with large archways, while the upper floor most likely housed public archives. Some time during the Middle Ages, it was said that a fortress was built over what remained of the Tabularium but was later transformed into the Palazzo Senatorio—a building that was used for administrative purposes. As well, between the 14th and 17th centuries, some of the rooms in the Tabularium were used for the storage and sale of salt. In contrast, some of the rooms were also used as prison cells up until the middle of the 19th century.

Sources:

“Tabularium | Musei Capitolini.” Www.museicapitolini.org, www.museicapitolini.org/en/infopage/tabularium.