Trinity County is a large, rugged and mountainous, heavily forested county located in the northwestern portion of the U.S. state of California, along the Trinity River and within the Salmon/Klamath Mountains. It covers an area of over two million acres (8,000 km²), and as of the 2010 census its population was 13,786, up from 13,022 at the 2000 census. The county seat and largest town is Weaverville, with a population of approximately 3,500 people.
Trinity County has one traffic light, no freeways, parking meters, or incorporated cities. Trinity County did not have a chain store or restaurant until 1999, when Burger King, Movie Gallery (closed), Longs Drugs (now CVS/pharmacy), and Subway opened for business.
Weaverville, the county seat, has the distinction of housing some of California's oldest buildings. The courthouse, built in 1856, is the second oldest in the state, and the Weaverville Drug Store has been filling prescriptions since 1852. The Joss House is an historic Taoist temple built in 1873.
The county takes its name from the Trinity River, named in 1845 by Major Pierson B. Reading, who was under the mistaken impression that the river emptied into Trinidad Bay. Trinity is the English translation of Trinidad.