Bonanza is a city in Klamath County, Oregon, United States near Klamath Falls. Take a look below for 10 interesting and obscure facts about Bonanza, Oregon, United States. 1. The population was 415 at the 2010 census. 2. Bonanza is at an elevation of 4,127 feet (1,258 m) in southern Klamath County near the Oregon–California…