Theatre of Pompey, remaining parts visible at Via dei Giubbonari 62, Rome. Roman columns and modern shops in medieval buildings.

Via dei Giubbonari (street of the jacket makers), Roman columns from the adjacent Theatre of Pompey. Later in the Middle Ages the square of Campo de' Fiori was built and the remaining parts of the theater were incorporated into medieval buildings or quarried to supply stone for many newer buildings which still exist in modern Rome.
While no longer the location of any workshops devoted to the lost art of jacket-making, this street still retains, at least partially, its original purpose as it is now a relatively important shopping street. It is probably the most visited shopping street in the Campo de' Fiori area.

The Theatre of Pompey (Latin: Theatrum Pompeii, Italian: Teatro di Pompeo) was a structure in Ancient Rome built during the later part of the Roman Republican era. It was completed in seven years, and was dedicated early in 55 BC before the structure was fully completed. It was one of the first permanent (non-wooden) theatres in Rome. The building itself was a part of a multi-use complex that included a large quadriporticus directly behind the scaenae frons. Enclosed by the large columned porticos was an expansive garden complex of fountains and statues. Along the stretch of covered arcade were rooms dedicated to the exposition of art and other works collected by Gnaeus Pompeius Magnus (English: "Pompey the Great") during his campaigns.

On the opposite end of the garden complex was a curia for political meetings. The senate would often use this building along with a number of temples and halls that satisfied the requirements for their formal meetings. This is infamous as the place of Julius Caesar's murder by the Liberatores of the Roman Senate and elite. Caesar was killed in the Curia of the Theatre of Pompey, and the spot he was believed to be assassinated is in the nearby square called "Largo di Torre Argentina".

more on https://en.wikipedia.org/wiki/Theatre_of_Pompey , https://en.wikipedia.org/wiki/Assassination_of_Julius_Caesar , https://en.wikipedia.org/wiki/Largo_di_Torre_Argentina