The Museo Alejandro de Humboldt (Alejandro de Humboldt Museum) is located in a Colonial house in Plaza de San Francisco de Asís Square, in Old Havana, Cuba. Its name comes from the German scientist Alejandro von Humboldt, who is seen as the second person to discover Cuba. This is a scientific museum dedicated to biology and its main objective is to preserve research and promote the historical Humboldt’s legacy. This institution enhances the labor of Cuban and international personalities whose contributions are considered relevant for the development of culture in general terms. It exhibits the historical trajectory of the scientific and botanic data he compiled throughout the island at the beginning of the 19th century, as well as a botanic exhibition which is fundamentally made up of ferns. In this museum there is a perfect copy of a Kritosaurus skeleton found in the desert and donated by the Mexican government, as well as an enormous Pterosaur skeleton, which is around 10 meters length. The House also has a conference room with capacity for 100 persons and a specialized library on German literature.

The Catedral Ortodoxa de Nuestra Señora de Kazán (Nuestra Señora de Kazán Orthodox Cathedral), declared World Heritage Site by UNESCO, is one of the newest constructions in Havana, being built in 2000. This Russian Orthodox church is Byzantine in style. It has six beautiful domes, two of which (the biggest and smallest) are gold-sheeted, and the rest are made of bronze. Its staircase entrance calls our attention and is considered the second largest staircase of all outside Russia. From the interior, its golden altar stands out, built in Trinidad and the San Sergio Monastery, Russia; and the murals adorning its walls.

The Santo Cristo del Buen Viaje Church is a simple yet charming church. It is located in Plaza del Cristo Square, on the western side of Old Havana, away from the city center and tourist areas. The structure of the church is intriguing because of the simplicity of its towers and of its lateral façades, in complete harmony with the character of the works of the 17th century. The church was built in 1732 in the same place where previously there was a Franciscan shrine. Nowadays it has only partially been restored, with its beautiful stained glass windows and brightly colored ceiling being very noteworthy qualities. Inside the church, the image of Jesus on the Cross among travelers and sailors became very popular because it was thought to keep people from harm. On Good Fridays the processions left from the Convento de San Francisco de Asís and ended at the Iglesia del Cristo. The dimensions of the plaza were planned according to the processions that were to take place in it, marking the end of the fourteen crosses or Stations of the Cross. The Plaza del Cristo Square is an ideal place if you want to get far from touristy areas and to witness what real Cuban life is like.

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.