🇮🇹 Italy · Submerged site
Portus Julius – Agrippa's Volcanic Naval Harbour at Lake Avernus
Roman Republican (37 – 12 BCE) · Roman Augustan (Agrippa)
Agrippa's 37 BCE volcanic-rim war harbour joining Lake Avernus to Lucrine Lake — causeway dam now –1 to –6 m under Lucrinus lagoon.