Walking through Rome you continuously encounter antiquities amidst the contemporary fabric of the city. Some are rather small, like the two fragments of Agrippa’s Baths projecting out of the street façade along the Via dell’Arco della Ciambella, while others cover large areas, like the Imperial Forums. And you assume that those ruins have been there since the buildings were built. And they have, of course (at least in most cases.) But there were not always open to view, but unexcavated under later buildings. Which means that whatever we encounter today is a more recent choice, a modern choice I would dare to say, of what gets uncovered and how it gets framed and displayed.
Take for example Largo di Torre Argentina, a large block with major antiquities including several temples dating from the Republican period, as well as remains of Pompey's Theater. It looks as if the ruins had been there open to view for the last couple millenniums. Now, look at the name of the street at the eastern edge of the block: Via di San Nicola de Cesarini. Interesting, isn’t it? Where is the church that gives the name to the street? Nowhere to be seen. As it turns out, that whole block of Roman antiquities was actually uncovered in the late 1920s--yes less than a hundred years ago!--as the Fascist government was actively reshaping the legacy of Ancient Rome for its own purposes (the area was actually inaugurated by Mussolini himself in 1929.) Only a few years earlier, you would have encountered not only the church of San Nicola but the dense medieval fabric surrounding it. Both the fabric and the church (marked with the number 883) can be seen in Nolli’s map of 1748.
(With thanks to my friend and colleague Ezio Genovesi, who first told me about this, as of so many other things in Rome.)