Basilica di San Giovanni in Laterano

This is Rome's actual cathedral, not St. Peter's, and holds the title "Mother of All Churches" for good reason. You'll find Borromini's surprisingly restrained white Baroque interior housing relics like pieces of the Holy Cross and John the Baptist's hair, plus Renaissance frescoes that most people walk right past. The 13th-century cloister is the real treasure - those twisted mosaic columns and carved medieval fragments create one of Rome's most peaceful spaces.

The experience feels more authentic than St. Peter's because it's still a working parish church. Locals drop in for prayer while tourists gawk at the massive papal altar and ornate ceiling. The cloister requires a separate entrance and feels like stepping into a medieval monastery - sunlight filters through the columns while ancient stone carvings tell biblical stories. The contrast between the austere nave and decorative side chapels keeps you discovering new details.

Most guides oversell the interior's grandeur compared to other Roman basilicas. The real payoff is the cloister (€2 entry), which rivals any in Europe but gets skipped by rushed visitors. Skip the museum upstairs unless you're genuinely interested in papal vestments. The baptistry next door is free and contains 5th-century mosaics that outshine anything inside the main church.