Beneath the outskirts of Rome lies the largest and possibly first set of burial tunnels. Dating back to the second century, the word ‘catacombs’ was first used in reference to the tunnels’ proximity to caves near the Appian Way. At one point, they contained the skeletons of hundreds of thousands of people, mainly early Christians in Rome who were often priced out of surface burials by the high cost of land. While 40 tunnels are known to exist, only 5 are currently open to the public. Scholars suggest there are many more tombs that lay undiscovered. Most bones have now been removed, but the catacombs continue to enrapture visitors keen to understand the early Roman empire.