The "Island of Death", as El Frontón is also known, was used since Colonial times as penal colony, penitentiary for common criminals and as a feared political prison. After the well-known prison riot in 1986, which was terminated by the military in a very bloody manner, the prison was finally closed.
Today El Frontón is only an immense rock formation in the ocean with deposits of marine salt and clay, but can be visited by interested sightseers.