Curia Julia
The Curia was one of the meeting places of the Roman Senate. The building standing in the forum today is a reconstruction carried out after a fire destroyed the previous one in 283 CE. In fact, the Curia was reconstructed many times throughout history. The most famous iteration of the Curia was the Curia Julia. The original Curia Julia was comissioned by Julius Cesar in 44 BCE to replace the Curia Hostilia, the original senate house in the Forum. Construction was completed under Augustus in 29 BCE. The building, as it is now, is fairly well-preserved due to the fact that it was converted into a Church for St. Hadrian in 630 CE. Much of the original decoration was removed either after the conversion of the building into a church or after the forum itself was abandoned, however a lot of the marble flooring remains impeccably preserved. The flooring is in the style of opus sectile, using pieces of colored stone to create geometric shapes. The wall decoration was similarly opulent, however some of it was removed due to its pagan connotations, or else looted after the abandonment of the forum when the Empire fell1.
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1.Amanda Claridge, Judith Toms, and Tony Cubberley Rome: an Oxford archaeological guide to Rome (Oxford: Oxford University Press, 1998).