The Havana Cathedral (also known as the Cathedral of The Virgin Mary of the Immaculate Conception, located in the Plaza de la Catedral) dates back to the mid-18th century built by the Jesuits. Most of the houses surrounding this plaza also date back to the mid-18th century.
Here’s a close up of the front of the cathedral. Notice the Baroque style facade. The materials used to build the cathedral came from the Gulf of Mexico. Apparently, if you look closely at the building facade, you should see marine fossils (I did not look closely enough).