Discover the Largest Forest in California (And What Lives Within It)

Lake Shasta, California
Devin Powers/

Written by August Croft

Updated: September 14, 2023

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The great state of California is home to countless native plants and animals, including redwood trees and much more. There are opportunities to explore the Pacific Ocean, desert regions, and plenty of forested areas, both large and small. You may even want to visit the largest forest in California, but where might this region be and just how large is it?

In this article, we’ll go over everything you need to know about the largest forest in California, including where it is located and how many acres it is. We’ll even give you some information about the history of this forest, what you can do there should you choose to visit, and the types of flora and fauna found within its groves. Let’s get started!

Infographic of the Largest Forest in California
From Castle Crags to Shasta Lake, the Shasta-Trinity National Forest brings together many types of natural areas.

The Largest Forest in California: The Shasta-Trinity National Forest

At over 2 million acres in size, the Shasta-Trinity National Forest is the largest forest in the entire state of California. It is located north of Redding and encompasses a huge swathe of Northern California, including the high-altitude Mount Shasta. In fact, there are more than 6,000 miles of running water in this forested region in the form of rivers. And this doesn’t even begin to address the large number of lakes and other mountains found in this region!

The Shasta-Trinity National Forest was once smaller and made up of two primary national forests. These forests were once named the Trinity National Forest and the Shasta National Forest. They have since been combined. This popular region in California hosts five different wilderness areas, including mountain peaks, rocky crags, and much more!

From Castle Crags to Shasta Lake, the Shasta-Trinity National Forest brings together many types of biomes and natural areas. Given the fact that it spans a wide swathe of California in between the Pacific coastline and mountains to the east, it’s a huge and fascinating regional area with plenty to offer the average recreational enthusiast. It’s certainly difficult to fathom 2 million acres, but California is large enough to boast a forest this large!

Largest Forest in California

The Shasta-Trinity National Forest includes Mount Shasta, which reaches over 14,000 feet high.

Where Is the Shasta-Trinity National Forest Located on a Map?

The Shasta-Trinity National Forest is between the upper Sacramento Valley and the Shasta Valley. Its lands are in parts of Trinity, Shasta, Siskiyou, Tehama, Modoc, and Humboldt counties. A nearby city is Redding.

History of the Shasta-Trinity National Forest

Given the fact that the Shasta-Trinity National Forest was once comprised of two separate forested areas, what is its history like? As early as 1905, President Theodore Roosevelt designated over one million acres in Northern California as the Trinity Forest Reserve. Later that same year, the Shasta Forest Reserve was also created. The two reserves were combined into the Shasta-Trinity National Forest in 1954. But this region of California was occupied long before our modern era.

Thousands of years ago, Native American tribes and groups occupied this region. The National Forest Service works in tandem with a dozen or more state and nationally recognized tribes to maintain the forest, which includes indigenous archeological areas as well as sacred monuments. There are many regions throughout the Shasta-Trinity National Forest that have evidence of inhabitants as long ago as 5,000 years!

Largest Forest in California

The Shasta Dam is part of the Shasta-Trinity National Forest.

Gold Rush Era

This forest also has plenty of history surrounding the gold rush times of the early 1800s. Given the fact that Mount Shasta reaches over 14,000 feet into the sky, it was a great landmark for travelers and pioneers crossing the nation in search of gold and a new life. Many people made it to California using landmarks found within this wilderness area. The Shasta-Trinity National Forest provided newcomers with plenty of timber, resources, and, of course, gold!

But copper was also an extremely popular ore mined in this region. In fact, multiple towns and settlements were created to mine copper in the 1800s. Nowadays, the majority of these towns no longer exist and are in fact sunk beneath the man-made waters of Shasta Lake! This dammed region was created in the 1940s. It also covers some remnants of the Oregon Trail as well as the Central Pacific Railroad.

What to Do in the Shasta-Trinity National Forest

If you are interested in visiting the Shasta-Trinity National Forest, there are a number of things you can do during your time there. Not only are there hundreds of miles of trails throughout this area, but there are also over 100 miles of the Pacific Crest Trail located in this forest, making it a great respite for those attempting this intense hike. Keep in mind that the Shasta-Trinity National Forest is located at multiple high elevations, making it subject to weather and seasonal conditions.

Besides hiking, you can bring along a boat or kayak to enjoy Shasta Lake. There are many different regions of the lake to explore, with some locations offering evidence and sightseeing of some of the aforementioned copper mining towns. You can camp throughout the forest as well, with fantastic campgrounds located at Castle Crags, near Lake McCloud, and plenty of sites surrounding Medicine Lake.

Speaking of Medicine Lake, this region is technically home to the largest volcano in California. These highlands offer visitors an insight into both volcanic activities as well as Native American history. With plenty of caves and waterways to explore, the Medicine Lake Highlands is worth the trip and truly brings a new perspective to the Shasta-Trinity National Forest!

Largest Forest in California

Visitors to the Shasta-Trinity National Forest can enjoy hiking, camping, and boating.

Wildlife in the Largest Forest in California

If you want to visit the Shasta-Trinity National Forest, you should be aware of what wildlife calls this region home. Given the fact that California is host to countless different wild species, this densely-forested region has plenty to offer the average wildlife enthusiast! Be prepared to combat ticks and mosquitoes if you should visit in the summertime. And always be aware of bears and cougars should you choose to camp or hike here!

Other wildlife that you might be able to spot here include:

Largest Forest in California

Always be aware of bears should you choose to camp or hike in the Shasta-Trinity National Forest.

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About the Author

August Croft is a writer at A-Z Animals where their primary focus is on astrology, symbolism, and gardening. August has been writing a variety of content for over 4 years and holds a Bachelor of Fine Arts Degree in Theater from Southern Oregon University, which they earned in 2014. They are currently working toward a professional certification in astrology and chart reading. A resident of Oregon, August enjoys playwriting, craft beer, and cooking seasonal recipes for their friends and high school sweetheart.

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