Both Havana and Santiago de Cuba have fortresses originally built to protect Spanish interests from raiders and pirates. While each as a longer name, both are usually known by the shorter name of Morro Fortress. The one in Havana is older, built in 1589 while the one in Santiago de Cuba was built in 1637. The styles are very different, as you can see from the photos.
Havana’s Morro Fortress
Santiago’s Morro Fortress