This atoll is southwest of San Andrés at . It is the westernmost point of Colombia. The reef is about across. In the southern part are Cayo del Norte and Cayo del Sur. Cayo del Norte, the larger of the two, is up to high and overgrown with palm trees and bushes. Cayo del Sur, a few hundred metres further South, reaches a height of a little more than and is vegetated with a few bushes, and in the South with mangroves. There is a lighthouse on Cayo del Norte, at , operating since 1980. It is maintained by the Colombian Navy.