Traverse five centuries along Naples’ engrossing Bourbon Tunnel. Conceived by Ferdinand II in 1853 to link the Palazzo Reale to the barracks and the sea, the never-completed escape route is part of the 17th-century Carmignano Aqueduct system, itself incorporating 16th-century cisterns. An air-raid shelter and military hospital during WWII, this underground labyrinth rekindles the past with evocative wartime artefacts. The standard tour doesn't require pre-booking, though the Adventure Tour (80 minutes; adult/reduced €15/10) and adults-only Speleo Tour (2½ hours; €30) do.
Tours also depart from Tunnel Borbonico's second entrance, reached through the Parcheggio Morelli (Via Domenico Morelli 40) parking complex in Chiaia.
