The Sierra Nevada de Santa Marta rise from the plains to snow-capped peaks, separated from the Andes as an isolated area of high biodiversity and endemism.

The main river is the Magdalena which is fully navigable in the region and a major path for the flow of shipments to and from inland Colombia.

The Guajira Peninsula is the most northerly point of South America and mostly desertic due to the rain shadow of the high Sierra Nevada de Santa Marta and is only crossed by the Ranchería River with no other major water courses in the area; thus water is scarce.

A small mountain range, the Serranía de Macuira, is located in the tip of the peninsula and contains a unique dwarf cloud forest completely surrounded by desert.

A small range of mountains called the Montes de María are found here and part of them are protected as the Los Colorados Sanctuary.