Recent underwater surveys in north-west Saudi Arabia identified 75 submerged heritage sites, including eight shipwrecks and two harbours. One harbour was identified in a sheltered bay facing the fort and settlement of al-Muwaylih, an important stop on the Egyptian Hajj route since the medieval period. Located about 40 km north of modern Duba, the site received grain shipments from Egypt and supplied passing vessels, as noted by travellers in the 18th–19th centuries. The survey documented an anchorage including four stone anchors, one of which represents the second recorded in the Red Sea attributable to the Indo-Arab type.
Zazzaro et al. (2026) studied this question.