It was built at the foot of Fort San Miguel in the 18th century.

Its function was to have a set of protected cannons to fire and prevent approach to the coast. 

It is very well preserved, and its rectangular plan is surrounded by a shallow moat and two bastions at the ends of the gate.

Additionally, there is a vestibule at the main gate, rooms, a kitchen, and sentry boxes facing the sea.

Currently, it houses the Secretariat of the Navy.