This is SO cool, and proof that you should never stop poking your nose into places it doesn’t belong, both metaphorically and physically speaking!
You see, the tunnels under Hadrian’s Villa at Tivoli were recorded by the archaeologists working at the site over a decade ago. But it’s a team of amateur archaeologists, who happen to also be avid, skilled spelunkers and speleologists (people who climb in, and study, caves), who have mapped out a network of underground rooms, passages, and even roads the likes of which no one had imagined would exist!!
Its a veritable underground city, covering hectares… possibly the entire 296 acres of the archaeological site, and possible even further. It’s even been suggested that there may be underground tunnels linking the entire underground complex at the Villa to other underground complexes such as those known to exist below Rome itself, over 18 miles away! The cavers were able to enter the underground warren through light shafts scattered around the fields surrounding the archaeological site, where they’ve found subterranean streets wide enough for ox-driven carts. Some of the spaces are filled with dirt collapsed from the roofs, so now robots have been called in to explore some of them, and excavations may follow.
This “chthonic city,” as one article refers to it, is hypothesized by the archaeologists to have likely been the habitat of the slaves, considered sub-human, who provided the manpower to run the mighty estates of the emperors, as well as the most meager households of common citizens. But by being underground, these subterranean sites have also been preserved in a way that those on the surface have not, and are increasingly recognized by archaeologists and amateurs alike as providing a wealth of knowledge about Roman society that otherwise would be lost to us. They may, of course, be a source of information about the lower, servile classes, who worked and possibly even dwelt hidden from the presence of the wealthy and powerful, and they also may shed light, despite their own darkness, on the operations of the cities and estates where the movers and shakers of Roman society lived and did business.