A part of the Great Rift Valley, Naivasha is a lush natural water lake that varies in size based on the rainfall, covering anywhere from 114 to 991 square miles. The general name Naivasha is a misspelling of the Masaai word Nai'posha, which means "rough waves" and refers to the strong waves that form on the lake during storms. Due in part to the rich waters and soil along the shore, the region is one of the chief agricultural areas of Kenya. The lake is surrounded by yellow fever tress which are home to a rich collection of birdlife, making the region a bird watcher's paradise.