A broken iron anchor, hundreds of years old, attests to a storm that foundered one of two ancient shipwrecks—from the mid-3rd and 14th centuries—which were discovered in the same location off the coast of Caesarea, Israel. Their antiquated cargos yielded nothing short of treasure preserved by the low-oxygen environment under the sea. While conducting an underwater survey, divers from the Israel Antiquities Authority’s Marine Archaeology Unit located the remains of two wrecked hulls scattered across the seafloor in shallow waters at a depth of about 4 meters, finding dozens of large bronze nails, lead pipes from a bilge pump, the said anchor, and a sounding lead for measuring the depth of the seafloor. Also produced were treasures from the ship’s cargo—including hundreds of silver and bronze Roman coins from the first to third century; a large hoard of about 560 silver dirham coins from the early 1300s, during the Mamluk period; a …