Perhaps the most iconic of all Cuban fortresses. Its construction began in 1589 and was completed in 1630, playing a key role in the defence of Havana against raids by corsairs and pirates.  When the English attacked and captured Havana in the year 1762, the castle was damaged and later as soon as Spain took power again it was rebuilt and modernized. A lighthouse was added to the Morro in 1764. Standing 45 metres above sea level, it has become an unmistakeable symbol of Havana.

The vast Fortaleza de San Carlos de la Cabaña, known as ‘La Cabaña’, running beside the harbor, was constructed after the English capture of Havana in 1763. The largest of the military structures built by Spain in the Americas, this fortress was completed in 1774 and its presence formed an effective complete deterrent against the country's enemies. The polygon, occupying an area of around 10 hectares, consists of bastions, ravelins, moats, covered walkways, barracks, squares and stores.  It is impressively well preserved, and the gardens and ramparts are romantically lit in the evening. This fortress hosts the spectacular nightly ceremony of El Cañonazo de las Nueve (cannon fire at 9), the firing of a cannon that marked the closing of the city gates, one of Havana's longest-held and most attractive traditions.

The San Francisco de Asís Church and Convent is the current scenario of the richest cultural traditions. This is one of the most extraordinary convent and church complex of the colonial time. The construction of the current set dates from 1738, and it replaced a more modest one completed in 1591. After a restoration in the nineties, the architectural group has harbored, also, a concert hall and the Holy, Sacred and Religious Art museums. The most significant element of the Church is the Tower 42 meters of height, second in altitude at the colonial time. 

Plaza de Armas surrounds a statue of the patriot Céspedes and is ringed by shaded marble benches and second-hand bookstalls. This square, founding in 1519, was the city's first open space, around which the most important political, military, religious and civil institutions were located. The palaces that surrounded it during the 18th century are worthy exponents of Cuban Baroque architecture. On the square’s eastern side a small neoclassical temple, El Templete, marks the spot where the first Catholic mass was celebrated in 1519. Next door is one of the city’s most luxurious hotels, Hotel Santa Isabel. To the north, the squat but angular and moated Castillo de la Real Fuerza (Fort of the Royal Forces) is one of the oldest forts in the Americas.