Columbia subject headings:
San Juan de Ulúa Island (Mexico)--History.
Veracruz (Veracruz-Llave, Mexico)--History.
Harvard subject headings:
Princeton subject headings:
Fortification--Mexico--San Juan de Ulúa Island--History.
San Juan de Ulúa Island (Mexico)--History.
Veracruz (Veracruz-Llave, Mexico)--History.