This area above the Customs House is now the car park for the Hotel Continental, but it once housed a battery of 29 canons pointed toward the sea. The canons date back to the Portuguese era, and have now been placed around the city. It was known as the Borj al-Salam until 1790, when it became known as Bordj Ben Allal, and in 1865 as Bordj Chachou. According to the page on the Borj in the
Inventaire et Documentation du Patrimoine Culturel du Maroc, they are the names of the Qaïds that commanded the battery.
SOURCES:
Roca, Juan Ramón. "Dar Baroud." In Tangier and Its Surroundings, Assilah and Chefchaouen an Illustrated Guide, 69. Alicante (C/ San Carlos, 93, 03013 Alicante): J.R. Roca, 2011.