Rome is full of hidden wonders, but few people know that deep under the Fori Imperiali lies a colony of giant freshwater crabs called Potamon fluviatile. These ancient crabs live in the old Roman canals beneath landmarks like Trajan’s Forum and the Basilica Ulpia. Scientists have studied how these urban crabs adapted to the underground environment, growing larger than their rural relatives. Though not visible to tourists, these crabs are an important part of Rome’s biodiversi