The Orinoco River and Venezuela's mountain ranges divide the country into some distinct regions, all with different climates.
The Maracaibo Lowlands of the far northwest are dry, windless and hot; the Andes Mountains and northern highlands are more temperate and much cooler in the higher elevations; the central plain fronting the Orinoco River covers about one-third of the country, most of it is less than 50 meters in elevation, and generally quite warm. The wild and largely unexplored Guiana Highlands covering the southeast, with elevations of up to 3,500 meters, are jungle-tropical, hot and very humid.
With over 10,000 rivers (mostly small) within its borders, the Orinoco is by far the most important. It's the third-longest river in South America, after the Paran and the Amazon; it has more than 2,000 tributaries - including the Apure, Arauca, Caron, Caura, Guaviare, Meta and Ventuari. Most of the other rivers that rise in the northern mountains flow southeastward to the Apure.
Significant lakes include Lake Guri and Lake Maracaibo, South America's largest lake.