Douglas City is a census-designated place (CDP) in Trinity County, California first settled during the California Gold Rush. Douglas City sits at an elevation of 2,152 feet (656 m). The ZIP Code is 96024. The community is inside area code 530. The 2010 United States census reported Douglas City's population was 713. The Whiskeytown–Shasta–Trinity National Recreation Area is nearby.
The prehistoric residents of the area were Wintun people; from North Fork to Douglas City the group was called Tien-Tien which means "friends". The Karuk called the same people the Kashahara. Local people suffered loss of population beginning with the epidemic of 1842. The explorer Jedediah Smith and his party came through the Hayfork area in 1828, killing several local people to intimidate the others and permit their passage.