The Catacombs of St Callixtus

Long before Christianity became Rome's official religion, the city's Christians buried their dead in underground cemeteries outside the walls, digging galleries into the soft volcanic tufa along the great consular roads. The Catacombs of St Callixtus, or San Callisto, on the Appian Way, are the most important of them. They take their name from Callixtus, a deacon who was put in charge of the cemetery around the year 200 and later became pope, and they grew into a vast network of passages on several levels, with burial places for a very large number of Christians, including many martyrs and early popes. Visits are by guided tour only, in small groups and in several languages, and they reveal only a fraction of the whole. You descend a staircase into a world of narrow corridors where the walls are lined with loculi, the rectangular niches in which bodies were laid and sealed with stone or tile, and family cubicula, small chambers with painted decoration. The highlight is the Crypt of the Popes, where several third-century bishops of Rome were buried and inscriptions bearing their names survive. Nearby is the crypt of St Cecilia, the Roman martyr and patron saint of music, whose body is said to have been found here before being moved to her church in Trastevere; a copy of a famous Baroque statue of her lies in the niche. Early Christian symbols, such as the fish, the dove and the Good Shepherd, appear on walls and tombstones. The site is run by the Salesian order on behalf of the Holy See, set in peaceful grounds of cypresses and pines, and the guides are knowledgeable and often moving in their explanations of how the early community lived, worshipped and remembered its dead.

Practical rhythm: tours depart regularly in different languages and last well under an hour; the Tiqets listing describes a tour of roughly forty minutes. According to current listings, the catacombs are open from morning to late afternoon with a midday break and are closed on Wednesdays, so plan around that, and check holiday closures. It is cool underground all year, which makes it a welcome escape on a hot summer day; bring a light layer. You must stay with your group, luggage, strollers and large bags are not allowed, food and drink are not permitted, and as a sacred site, shoulders and knees must be covered.

Getting there: the entrance is on the Via Appia Antica, outside the walls south of the centre, and the simplest options are a bus toward the catacombs or a taxi. Many visitors combine the catacombs with a walk or bike ride along the Appian Way, which passes right by: the Tiqets venue page also lists tours with transfers from the centre and longer tours that combine the catacombs with the ancient road and the Roman countryside. If you plan to cycle the Appia, visit the catacombs first, before you get hot and tired, and lock bikes outside.

Who it suits: for history buffs and anyone interested in the origins of Christianity, this is one of the most meaningful sites in Rome, and it is far less crowded than the Vatican. Children usually find the underground passages exciting, though very young children may feel enclosed, and anyone with claustrophobia should know that some galleries are narrow and low. Photography rules are strict underground. Pair it with the Baths of Caracalla on the way out of town, or with the Capuchin Crypt in the centre for a day exploring how Romans of different ages faced death.