Located in Barbate and Zahara de los Atunes, Spain, it protected the local Almadraba tuna traps as well as having a wider strategic role.

In 1294, King Sancho IV of Castile granted a licence to Don Alonso Pérez de Guzmán to build traps for tuna fishing in reward for his heroic defense of Tarifa.

Its location at a strategic point of the Strait of Gibraltar has been given prominence in numerous historical events, and it maintains a continued presence in coastal mapping.

The main gateway is located in the west wall, the two sea gates are in the south, which originally also provided access to large patio inner enclosure of the building.

In the twentieth century 'New Gate' was added in the north wall, where there are also various other piercings introduced for practical reasons as the use of the building developed over time.