Largo di Torre Argentina
The name of the square comes from the Torre Argentina, which takes its name from the city of Strasbourg, whose Latin name was Argentoratum. In 1503, the Papal Master of Ceremonies Johannes Burckardt, who came from Strasbourg and was known as "Argentinus", built in via del Sudario a palace (now at number 44), called Casa del Burcardo, to which the tower is annexed.
The other tower in the square is not the one giving the name to the place, but the Medieval Torre del Papito ("Little Pope's Tower"), attributed by tradition to Antipope Anacletus II Pierleoni, allegedly not a tall person.
After Italian unification, it was decided to reconstruct part of Rome (1909), demolishing the zone of Torre Argentina. However, during the demolition work in 1927, the colossal head and arms of a marble statue were discovered. The archeological investigation brought to light the presence of a holy area, dating to the Republican era, with four temples and part of Pompey's Theater.
The four temples, originally designated by the letters A, B, C, and D, front onto a paved street, which was reconstructed in the imperial era, after the fire of AD 80. The area was delineated to the North by the Hecatostylum (one-hundred columns porch) and the Baths of Agrippa, and to the South by the buildings related to the Circus Flaminius, to the East by the great porched square of Porticus Minucia Frumentaria, and to the West by the Theatre of Pompey.
Temple A was built in the 3rd century BC, and is probably the Temple of Juturna built by Gaius Lutatius Catulus after his victory against the Carthaginians in 241 BC. It was later rebuilt into a church, whose apse is still present.
Temple B, a circular temple (tholus) with six columns remaining, was built by Quintus Lutatius Catulus in 101 BC in fulfillment of his vow at the Battle of Vercellae. The temple (aedes) was devoted to Fortuna Huiusce Diei, "the Fortune of This Day." The colossal statue found during excavations and now kept in the Capitoline Museums was the statue of the goddess herself. Only the head, the arms, and the legs were of marble: the other parts, covered by the dress, were of other materials, probably a wooden frame. This is known as an 'acrolithic' statue
Temple C is the most ancient of the three, dating back to 4th or 3rd century BC, and was probably devoted to Feronia the ancient Italic goddess of fertility. After the fire of 80 AD, this temple was restored, and the white and black mosaic of the inner temple cell dates back to this restoration.
Temple D is the largest of the four, dates back to 2nd century BC with Late Republican restorations, and was devoted to Lares Permarini, but only a small part of it has been excavated (a street covers the most of it).
18th century opera house
The Teatro Argentina was an 18th-century opera house and theatre located in the square. The premieres of many notable operas took place there. They include Gioachino Rossini's The Barber of Seville in 1816 and Giuseppe Verdi's I due Foscari in 1844 and La battaglia di Legnano in 1849.
The cat shelter
Located in Largo Argentina is the Torre Argentina Cat Sanctuary, a no-kill shelter for homeless cats (of which Rome has many), as the historical area abounds with various breeds of cats. The cat sanctuary has recently been requested to close due to perceived health concerns. 
- This identification is preferred over the one as Temple of Iuno Curritis, because Ovid (Fasti I) says: "Te quoque lux eadem Turni soror aede recepit/Hic, ubi Virginea Campus obitur aqua", thus posing the temple of Juturna near the Aqua Virgo, which ended at the Baths of Agrippa.
- Paddy Agnew, "Cat sanctuary at Roman site could be clawed away", November 2, 2012
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