One of the more charming examples of Rome’s lesser-known, world-class sights is this monumental complex of a late imperial burial chamber, an early Christian basilica, and, for good measure, some catacombs. The fourth-century mausoleum of St. Constance (Constantine the Great’s daughter) is more delightful than morbid and features well-preserved ceiling mosaics with an intriguing blend of pagan and Christian motifs and unique architectural forms. The adjacent church of St. Agnes “Outside the Walls” was dedicated in the fourth century shortly after Agnes was martyred by beheading, and was rebuilt in the seventh century. Her body is said to lie in the catacombs beneath (minus the head, which is preserved in a transparent glass reliquary at the church of Sant’Agnese in Agone, in Piazza Navona!), through which a guide leads tours every half hour. As if these cultural attractions weren’t enough, there’s also an action-packed bocce club (with coffee bar) around back, where old-timers duke it out with great flair and don’t mind spectators. The bus ride out here takes you past elegant 19th-century palazzi on sycamore-lined Via Nomentana, one of the original consular roads that famously led to Rome.

Insider Tip: Although the posted schedule says that the Mausoleum is open 4-6 p.m., it’s frequently used for weddings, so don’t count on being able to get inside in the late afternoon.

Open Monday 9 a.m.-12 p.m., Tuesday-Saturday 9 a.m.-12 p.m. and 4 p.m.-6 p.m., and Sunday 4 p.m.-6 p.m. No charge to enter mausoleum and basilica; $7.50 to visit catacombs.