The name Longonot is derived from the Masai word Oloonong'ot meaning mountains of many spurs or steep ridges. Longonot park covers 52 km2 most of it being occupied by Mt. Longonot a young volcano rising to 2,776 meters above sea level. The sides of the mountain have beautiful V-shaped valleys and ridges. The stony soils have little vegetation but the crater has an impenetrable forest.
The climate is hot and dry. Mean annual rainfall is between 510 to 760mm. Rainfall reliability is poor and unpredictable. The annual mean maximum temperature is usually between 26 to 30c.