Emerald Triangle

The Emerald Triangle refers to the three counties of Mendocino, Humboldt, and Trinity in Northern California, United States.

This region is also called Behind the Redwood Curtain, because the two major highways that connect these three counties, U.S. Route 101 and State Route 299, are narrow, winding and lined with tall redwood trees. This cuts the Emerald Triangle off from the rest of California.

Also refers to the three biggest marijuana producing counties in California and also the USA.

The three counties are known for their general libertarian politics and historical dependence on the timber industry. They were also associated with various ill-fated plans to secede from California and become, along with several counties in neighboring Oregon, a part of the proposed State of Jefferson.

Additionally, Emerald Triangle is part of the title of Thailand's Emerald Triangle, a book by Lawrence Whiting about the Ubon, Sisaket provinces and the unique geographical triangle where Thailand, Cambodia and Laos meet.