city, Los Angeles county, California, U.S. It lies at the base of the San Gabriel Mountains. The region had been inhabited by Tongva (or Gabrielino) Indians before it became part of the original Mission San Gabriel Arcángel holding. The city was laid out in 1888 on lands of what by then had become the privately owned Rancho Santa Anita. It was developed by E.J. (“Lucky”) Baldwin and named for the district in ancient Greece said to symbolize pastoral beauty (see Arcadia). An early agricultural centre, the city contained many chicken and horse ranches and fruit groves; it was later promoted as a residential community. Arcadia was often devastated by winter floods until the 1930s, when flood controls were built. Freeway connections to Los Angeles, some 15 miles (25 km) southwest, aided its growth. Arcadia is the site of the Los Angeles County Arboretum and Botanic Garden and the Santa Anita Park racetrack. Angeles National Forest, north and east of the city, is a popular recreational destination. Inc. 1903. Pop. (1990) 48,284; (2000) 53,054.

mountainous region of the central Peloponnesus of ancient Greece. The pastoral character of Arcadian life together with its isolation partially explains why it was represented as a paradise in Greek and Roman bucolic poetry and in the literature of the Renaissance. The region is not exactly coextensive with the present-day nomós (department) of Arkadhía, which extends on the east to the Gulf of Argolis. The capital of the nomos is Trípolis.

The plateau of Arcadia, with basins at elevations of 1,650 to 3,300 feet (500 to 1,000 m), is bounded on the north by the Erímanthos and Killíni mountains and is itself divided by numerous subsidiary ranges. In eastern Arcadia the ranges enclose a series of plains drained only by underground channels. The western plateau is more open, with isolated mountains through which wind the Alpheus River and its tributaries. One of those, the Ládhon, provides hydroelectric power at a dam and reservoir. A region of erratic rainfall, Arcadia has a few vineyards but no olive trees. There are patches of oak forest, but the eastern reaches are drier and less verdant.

In ancient times Arcadia was bounded on the north by Achaea, on the south by Messenia and Laconia, on the east by Argolis, and on the west by Elis. It was thus cut off from the coast on all sides. Because it was isolated from the rest of mainland Greece, Arcadia was not occupied by the Dorians (Dorian) during their invasion of Greece (1100–1000 BC), and it retained a dialect that still resembles that of the Greeks who settled in Cyprus (the Arcado-Cypriot dialects). By 550 BC Tegea, Mantinea, and the smaller Arcadian towns had all accepted forced alliances with Sparta, and discord between the towns subsequently prevented them from uniting against Spartan power. Most Arcadians remained faithful to Sparta during the Peloponnesian War (431–404 BC), though in 370 BC the Arcadian League, with its capital at Megalopolis, united the Arcadians for a few decades before internal discord paralyzed their confederation. In Roman times Arcadia fell into decay. It was a scene of conflict during the War of Greek Independence (1821–29). Area 1,706 square miles (4,419 square km). Pop. (1981) nomós, 107,932; (1991) nomós, 105,309.