Glendale (Wiyot: p'lÃ¨ta-kawÃ¨ti rocks-white ) is an unincorporated community in Humboldt County, California. It is located on the Mad River 4 miles (6 km) east-northeast of Arcata, at an elevation of 92 feet (28 m). ^ U.S. Geological Survey Geographic Names Information System: Glendale, Humboldt County, California.