Deep in the heart of Rome’s largest catacombs, laser beams have unveiled stunning 1,600-year-old early Christian frescoes. Mixing pagan symbols with Christian images, the paintings adorn the ceilings and walls of two burial chambers in the Catacombs of Domitilla, a labyrinth of tunnels and tombs stretching over 10 miles beneath Rome near the ancient Appian Way. The crypts, carved out of volcanic tufa, were created for wealthy merchants involved in the imperial grain trade and the production of bread. They were painted around A.D. 360, a few decades after the emperor Constantine declared Christianity legal. “The chambers have long been known, but laser cleaning has removed centuries of grime, algae, and chalk, revealing elaborate scenes and new findings,” says Fabrizio Bisconti, the superintendent in charge of catacombs for the Vatican’s Pontifical Commission for Sacred Archaeology.