This article searches for the historic centre of Los Angeles, California, the archetype of urban sprawl. Taking maps and photographs as its principal sources it finds an enduring urban centre in a plaza designed by the Spanish in 1781 and occupied by Mexicans until the US army conquered the city in 1847. The Plaza anchored the dispersed ranch land of the Pueblo of Los Angeles and was the magnet for commercial development during the first decades of American settlement. Between 1850 and 1880, Anglo immigrants built up the south-western side of the Plaza with shops and civic buildings creating a hybrid and bicultural centre, a compression of Main Street and the Plaza. After 1880 a process of spatial mitosis occurred as commerce and municipal functions moved down Main Street and melded into a modern downtown. Since then the skyscrapers downtown have overshadowed but not displaced the old Plaza, which still serves as social, symbolic and ceremonial space for Angelenos, especially immigrants from Latin America. The durability of the Plaza and its direct successors, Main Street and Downtown, not only designate a centre for Los Angeles, but articulate a distinctive urban morphology, that of a centrifugal metropolis rather than fragmented city or sprawl of suburbs.