Situated very near  Havana Bay, the Castillo San Carlos de la Cabaña is  the  biggest military fortress built  in Cuba and the American Continent.  It started to  be built in November, 1763 and the  works were finished in December, 1774.

It has an  extension of 700 meters of external polygon and ten hectares of land and represents the  most outstanding work of  the military construction system. San  Carlos de la Cabaña was protected by military corps  of the Spanish Crown elite in accordance with  its strategic importance and its  role as prison.

Beyond its history and features, this ancient military fortress of the colonial epoch has a great significance,  particularly in Havana, as the traditional Ceremonia del Cañonazo takes place at 9 pm every night.

The 9 O´Clock Cannon Fire  dates from colonial times when the Havana Historical Center was surrounded by  big walls and the fire indicated that the walls would be closed.

The San Carlos de la Cabaña fortress is part of  the works that have  been declared  humanity cultural heritage by The United Nations Organization for  Education, Science, and Culture.

The 9 O´Clock Cannon Fire  is a singular ceremony which takes place at night every night in the capital city and is a great attraction at present for Cubans and for foreign visitors. This ceremony takes place at San Carlos de la Cabaña which is the biggest ancient  military fortress of colonial times in Cuba.