🇮🇹 Italy · Submerged site
Cosa – Tagliata Etruscan–Roman Harbour & Spacco della Regina
Etruscan to Medieval (273 BCE colony – 1320 CE sack) · Etruscan / Roman Republican / Imperial
Etruscan-cut Tagliata channel port — 70 m rock-cut harbour canal now tidal 0–1 m, Rome earliest colony harbour.