napoli - cunicolo di areazione della grotta di seiano

2020 accessibility ancient arch archaeological arches architecture archway avenue bagnoli bourbon built campania cave connection connects coroglio dark della engineering february gaiola gallery geological grotta gulf hill historical imperial ingresso interno italy long mediterranean naples napoli parco park particolare path pollione posillipo reinforcement roccia rock romans seiano site that trentami tufa tuff tufo tunnel underground villa virgiliano