Mountainous areas cover only about one quarter of the island and are widely separated. In the west the Sierra de los Organos are characterized by curious limestone hills shaped like organ pipes. There are more than 280 white-sand beaches. Hundreds of pouch-shaped bays and inlets provide many fine harbors, including Guantanamo Bay in the southeast, which was leased by the United States in 1903 for use as a naval base and is still under American control. There are more than 200 short, swift rivers.
Seasonal flooding is common.
Only the Rio Cauto is navigable for a short distance. The surrounding bodies of warm water and the mild northeasterly trade winds moderate Cuba's tropical climate. It is heaviest from May to June and from September to October. Hurricanes pose a threat from July through October. Agriculture Cuba's leading industry is agriculture.