Set in its own secluded grounds, this haunting church boasts a porticoed facade and a round, columned interior. But what really gets the heart racing is the graphic wall decor – a cycle of 16th-century frescoes depicting the tortures suffered by many early Christian martyrs.
Describing the frescoes in 1846, Charles Dickens wrote: 'Such a panorama of horror and butchery no man could imagine in his sleep, though he were to eat a whole pig, raw, for supper.' The church, one of Rome’s oldest, dates from the late 5th century, although it was subsequently altered in the 12th and 15th centuries.