Orography
Cuba rides on a separate tectonic plate, which originally was in the Pacific Ocean but (after crossing between the then separated Americas) crashed into Florida. This along with several other violent events (including volcanic activity, the crash of the comet Chicxulub, and earthquakes the Sierra Maestra is immediately north of the Bartlett Deep, or Cayman Trench on the main Caribbean Plate) fractured huge slabs of rocks. Enormous tsunamis presumably from the volcanoes on the Canary Islands carved great steps on the coast. All this caused emergence of these mountains in a complex process that included lifting up of now cave-ridden calcareous deposits, and the development of the Bartlett Deep or Cayman Trough. Originally heavily forested and divided by deep river valleys, volcanic dykes, and impassable karst areas, its steep valleys and abrupt fault lines make it an ideal terrain for rebellion.
Read more about this topic: Sierra Maestra