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All your future shipments deliver an extra fishing boat. Grants 1 Red Sea Wagon.
—In-game description

Somali Berbera Seaport is a technology in Age of Empires III: Definitive Edition - The African Royals that can be researched at a Trading Post built on a Somali settlement. Once researched, a Red Sea Wagon appears at the Home City shipment point and a Fishing Boat will be given with every Home City shipment sent after the technology is researched.

Somali Berbera Seaport is not available if the map where the Somali settlement appears has no bodies of water (i.e. landlocked maps).