You can take a virtual tour of the catacombs here: catacombe.roma.it/
Fundamentalists should ponder that the catacombs are extant witnesses to the tradition of the Catholic Church from its earliest times. On the walls, mortuaries and chapels, we find living proof of the antiquity of Catholic tradition and belief in the Primacy of Peter, baptism, penance, Holy Eucharist, the veneration of Saints and Martyrs, Mary, prayers for the dead, the sacrifice of the mass, and purgatory.
Making the fundamentalists conform to the faith of the catacombs is an impossible task. Fundamentalist should be challenged to prove that their 16th century doctrines are in conformity with the real early church of the catacombs.