Arcadia is a city in Los Angeles County, California, United States, and located approximately 13 miles (21 km) northeast of downtown Los Angeles in the San Gabriel Valley and at the base of the San Gabriel Mountains.
Arcadia is part of a cluster of cities, along with Temple City, Rosemead, Monterey Park, San Marino, and San Gabriel, in the west San Gabriel Valley with a growing Asian population. It is the site of the Santa Anita Park racetrack and home to the Los Angeles County Arboretum and Botanic Garden. As of the 2000 United States Census, the city had a population of 53,248. The estimated 2005 population was 56,565. The city is named after Arcadia, Greece.