The Klamath Mountains are a mountain range in northwest California and southwest Oregon, the highest peaks being Thompson Peak (2744m / 9002') in Trinity County, California, and Mount Ashland (2296m / 7533') in Jackson County, Oregon. They have a very varied geology, with substantial areas of serpentine and marble, and a climate characterised by cold winters with very heavy snowfall, and warm summers with limited rainfall. As a consequence of the geology, they have a unique flora including several endemic or near-endemic species, such as Lawson's Cypress (Chamaecyparis lawsoniana), Foxtail pine (Pinus balfouriana), Brewer's Spruce (Picea breweriana) and Kalmiopsis (Kalmiopsis leachiana). The northern portion of the Klamath range is also known as the Siskiyou Mountains.
