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 (with Humboldt being the most well known), and also the USA.


