Big Sur is a lightly populated region of the Central Coast of California where the Santa Lucia Mountains rise abruptly from the Pacific Ocean. Although it has no specific boundaries, many definitions of the area include the of coastline from the Carmel River in Monterey County south to the San Carpoforo Creek in San Luis Obispo County, and extend about inland to the eastern foothills of the Santa Lucias. Other sources limit the eastern border to the coastal flanks of these mountains, only inland. Another practical definition of the region is the segment of California State Route 1 from Carmel south to San Simeon. The northern end of Big Sur is about south of San Francisco, and the southern end is approximately northwest of Los Angeles.