- Historical significance: One of the oldest and largest Christian burial sites in Rome, often called “the little Vatican” due to the many popes buried there.
- Time period: Established in the 2nd century AD and named after Pope Callixtus I.
- Art and architecture: Early Christian frescoes depicting biblical scenes. Symbolic engravings of fish, doves, and anchors, representing faith and salvation.
- Current use: Popular site for pilgrimage and historical tourism.
- Accessibility: No
- Key features: Burial site of 16 popes and many martyrs; Crypt of St. Cecilia, patron saint of music, known for her evocative statue; Extensive network of underground corridors with loculi (niches for bodies) and cubicles (family tombs).