Hoopa is an unincorporated community and census-designated place in Humboldt County, California. It is located 10 miles south of Weitchpec, at an elevation of 328 feet. The ZIP Code is 95546. Hoopa is a rural town located entirely on the federally-designated reservation of the Hupa and serves as the administrative capital of the Hoopa Valley Indian Reser…Hoopa is an unincorporated community and census-designated place in Humboldt County, California. It is located 10 miles south of Weitchpec, at an elevation of 328 feet. The ZIP Code is 95546. Hoopa is a rural town located entirely on the federally-designated reservation of the Hupa and serves as the administrative capital of the Hoopa Valley Indian Reservation. Hoopa is on the Trinity River. Hoopa is in area code 530.