The Cristo Velato (Veiled Christ) by Giuseppe Sanmartino (1753) is the most technically astonishing sculpture in Italy. Christ lies on a marble bed, covered by a marble veil — but the veil is so thin, so transparent, so impossibly delicate that you can see veins, ribs, the wound in his side, and the texture of skin THROUGH THE STONE. Your brain cannot process that it's marble. You stand in front of it and your hand reaches out involuntarily to check if the veil is real fabric. It isn't. It's stone. One sculpture justifies the trip to Naples. Naples museums →
Via Francesco de Sanctis 19/21 (off Spaccanapoli, no external signage — look for the queue). €10. Open Wed-Mon 9am-7pm. Book online (museosansevero.it) to skip the queue — the chapel is TINY (one room) and limits visitors. Cristo Velato — center of the nave. Walk around it. Look at the feet (the veil pools around the toes). Look at the face (the closed eyes visible through stone mesh). The veil is carved from the SAME block of marble as the body — it's not a separate piece applied on top.
Il Disinganno (Antonio Corradini, 1752) — a man freeing himself from a marble NET. The net is carved from stone. Every knot, every mesh hole, every strand of rope = marble. Pudicizia (Modesty) (Corradini, 1752) — a veiled woman, predecessor to the Cristo Velato technique. Anatomical Machines (basement) — two human skeletons with their entire circulatory systems preserved/reconstructed in metal wire (18th century). Creepy, fascinating, pre-modern medical science at its most obsessive.
Visit time: 30 minutes (small space, but you'll stand in front of the Cristo Velato for 10 of them). No photos allowed (enforced). Combine with: Walk 5 min to MANN (Via dei Tribunali → Piazza Museo) → pizza at Sorbillo (2 min from MANN). The perfect Naples morning: Sansevero 9am → MANN 10am → Sorbillo 1pm.