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Explore the Region

jed smith

Breathtaking beauty and untouched serenity are only a small part of what makes the Klamath-Siskiyou region so unique.

Teeming with life, the Klamath-Siskiyou is ranked one of the most biologically diverse regions in the world. From the Pacific coast, the rain-soaked coastal redwood forests give way to the rugged Klamath Mountains, which are bordered on the east by the arid foothills of the Rogue and Shasta Valleys. Wild salmon and steelhead spawn in the pristine Wild and Scenic Rivers, while the clear, cold streams provide fresh drinking water for our local communities.

The Klamath-Siskiyou region’s dense mountain forests and beautiful rivers provide a recreational wonderland for generations of families to enjoy and pass on.

The federally-protected Wilderness Areas, National Recreation Areas, National Forests, National Parks, and Wild and Scenic Rivers ensure that this national gem will remain for our future generations to treasure.


pilot rock flowersFrom north to south, four mountain ranges span the Klamath-Siskiyou region: the Siskiyous, Marbles, Trinity Alps, and Yolla Bollys. Geologists call these mountains the “Klamath Knot,” because they all have one thing in common: they are composed of a complex variety of rocks largely untouched by glaciers.

Geologists believe these mountains were created about 200 million years ago when the North American plate and the Pacific plate collided.  The heavier Pacific plate dove (subducted) underneath the North American plate, scraping layers of the ocean floor onto the edge of the continent. The pressure from this event thrust up mountains made of the ocean floor.  Over millions of years, surface sediments were transformed by heat and pressure, becoming metamorphic schist and gneiss.

Over time, these mountains eroded into rolling hills, until 3 million years ago when the great plates slipped sideways and split the ranges into large, upturned fault blocks.  These became the steep, water-carved canyons we see today.

The terrain is rugged, and its abrupt changes in geology, soils, elevation, slope, aspect, and moisture are the leading reason for the region’s incredible diversity and variety.


biodiversity flowerThe Klamath-Siskiyou’s world-class biological diversity makes it one of the most unique ecosystems in the world.

The great diversity and age of the region’s underlying geology and soils, as well as its geographic location, account for the Klamath Siskiyou’s astounding biodiversity.

Positioned at the junction of the uplifted Coast Ranges, the volcanic Cascades, and Sierra Nevadas, the Klamath-Siskiyou was spared the vulcanism and glaciation that occurred around them, thus making the region a refuge for plant and animal species from all directions.

Not only is it home to 3,500 plant species, but nearly 300 of them exist nowhere else on Earth. The region also contains 36 species of conifers, more than any other temperate forest region in the world.


redwoods kidsLarge, majestic and varied, the forests of the Klamath-Siskiyou are both awe-inspiring and biologically fascinating.

Thirty-six conifer species exist in the Klamath-Siskiyou, more than anywhere else in North America and possibly the world. In a one-square-mile area of the Russian Wilderness alone, 17 conifer species are found – the highest diversity of conifers ever recorded at a single site.

The rain-soaked coastal redwood forests in the west contain the tallest trees on Earth, attracting tourists from all over the world.

Ancient tree species found nowhere else on Earth include the Brewer spruce and Port Orford cedar, both survivors of the ice age.

Experience the Klamath-Siskiyou and discover what makes this region a national treasure.


salmonThe beautiful, healthy rivers of the Klamath-Siskiyou region bring countless benefits to the local communities.

Every year, tens of thousands of people flock to these rivers, like the Rogue, Klamath, Salmon, and Smith, to raft, fish, hike and to just enjoy their inherent beauty.

The Siskiyou Wild Rivers in the Oregon part of the Klamath-Siskiyou is home to the most iconic aquatic species in the Pacific Northwest: the Pacific Salmon. Native salmon and steelhead in the Rogue River watershed alone bring more than $1.5 billion to the local economy each year.

Whether you love to enjoy river recreation or just a nice glass of fresh drinking water, the clear cold rivers in the watersheds of the Klamath-Siskiyou are valuable and important.


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