Glenn County was formed in 1891 from parts of Colusa County. The county was named after prominent citizen Hugh J. Glenn, who was the state's largest wheat farmer at the time. Today the county remains an agricultural area, with a population of just 29,000 operating nearly 1200 farms that produce rice, almonds, milk products, prunes and livestock.
- 1 Tehama County - Glenn County's northern neighbor, Tehama County has a quintessentially "western" feel, with most county residents employed in ranching, timber or farming, and most tourists drawn to the region for fishing, boating, hiking, and other outdoor activities. The county's largest town, Red Bluff, has a population of only about 15,000 inhabitants, but hosts the Red Bluff Round-Up, one of the west's largest annual rodeos, each spring. While there are numerous streams and rivers, the Sacramento River is the largest, intersecting the county and offering excellent fishing for rainbow trout, king salmon, chinook salmon, steelhead, smallmouth bass, sturgeon, and striped bass.
- 2 Butte County - Named for the Marysville Buttes that are actually found in neighboring Sutter County, Glenn County's eastern neighbor is a rural destination featuring rolling hills, rivers, and large agricultural areas. The town of Chico is a college town that is home to many excellent restaurants, massive Bidwell Park, and the National Yo-Yo Museum. The town of Oroville boasts a downtown area that dates back to the Gold Rush, and is now home to America's tallest dam (tours available), behind which sits a reservoir that is enjoyed by boaters and hikers. Further afield, 410 ft (120 m) tall Feather Falls rewards hikers willing to traverse the 8 mi (13 km) loop trail.
- 3 Colusa County - Located south of Glenn County, visitors to rural Colusa County will find an abundance of rice fields and almond trees, but a limited number of amenities and attractions. Sights that may be of interest include four national wildlife refuges, as well as the Colusa County Courthouse in the town of Colusa, which was erected in 1861 and is the oldest remaining courthouse in the Sacramento Valley.
- 4 Lake County - Rural Lake County lies southwest of Glenn County and is named after Clear Lake, a body of water that is believed to be 2.5 million years old and thus the oldest lake in North America. The lake is sometimes called the "Bass Capital of the West", and its 100 miles of shoreline offer ample opportunity for fishing, boating, swimming and birdwatching. The county is also home to the Clear Lake Volcanic Field, a region that includes lava domes, cinder cones, the 4,305 foot tall volcano Mount Konocti, and the world's largest geothermal field with more than twenty geothermal power plants.
- 5 Mendocino County - Lying halfway between San Francisco and the Oregon border, Glenn County's western neighbor boasts redwood forests, wineries, breweries, and remote, untouched coastline. In addition to its natural features, the county is home to the largest Buddhist Temple in the Western Hemisphere, the 400+ acre City of Ten Thousand Buddhas in Ukiah. The Mendocino Coast Botanical Gardens, located near Fort Bragg, is a 47 acre public garden with oceanside views. While hikers and backpackers will find no shortage of options, those looking for less strenuous ways to enjoy the scenery can ride the Skunk Train, a railroad that has been in operation since 1885 and takes riders 40 miles through old growth forests and across historic trestles between Fort Bragg and Willits.