The sinkhole, located in the Piazza della Rotonda, is almost 10 square feet (1 square meter) big and just over 8 feet (2.5 m) deep. Inside the hole, archaeologists found seven ancient slabs made of travertine, a type of sedimentary rock. Luckily, no one was hurt when the sinkhole collapsed on the afternoon of April 27, because the normally crowded piazza was empty due to the COVID-19 pandemic. Sinkholes like this one, however, are becoming an increasingly common problem in Rome. The stones uncovered by the sinkhole were created around the same time that the Pantheon was built, from 27...