These catacombs were once known as the Church of Rome’s cemetery and the crypt contain the tombs of nine popes. It covers an area of approximately 20km on four floors and probably the most visited are the papal crypt and Santa Cecilia’s sepulchre. They were discovered by accident by Giovanni Battista de Rossi who came upon two unusual structures in a vineyard. He acquired the land and started excavating, finding various relics before uncovering the catacomb complex.