Duarte (/ˈdwɑrtiː/ or /duːˈɑrteɪ/; from Spanish or Portuguese [ˈdwaɾte]) is a city in Los Angeles County, California, United States. As of the 2010 census, the city population was 21,321, down from 21,486 at the 2000 census.It is bounded to the north by the San Gabriel Mountains, to the north and west by the cities of Bradbury and Monrovia, to the south by the city of Irwindale, and to the east by the cities of Irwindale and Azusa.Duarte is located on historic U.S.