It is one of the oldest access gates to the Military Arsenal, known as the Carlos III Gate. It was built in the mid-18th century and rebuilt in 1857. The other Arsenal gates are called Dique (dike) and Parque (park). The Puerta del Dique (Dike Gate) is crowned by the coat-of-arms of Carlos III and a clock which marked the pace of the works at the Arsenal, but also of the city.
The city of Ferrol became more important when it was designated the capital of the maritime Department of the North (1726) and with the construction of the Arsenal between 1752 and 1770. The Arsenal served various purposes related with the navy, from shipbuilding to all the logistics related therewith and military control and defence. For its protection a large dock was built, defended by a powerful jetty armed with a cannon battery. It was surrounded by a large wall and a moat which separated it from the rest of the city. The moat was closed off in the late 19th century.
The Arsenal is endowed with architecture that ensures functionality and form, resulting in a striking work. The Arsenal was intended to show the power of the monarchy and to serve as a symbol of the greatness of the State. The district of La Magdalena was erected opposite the Arsenal, also designed by military engineers.
At present the shipyards of the Company Navantia are situated here. It was declared Heritage in the Cultural Interest and can be visited.