 San Diego is by far the most populated county though population density is much higher in the immediate border area adjacent to the south in Baja California than it is in San Diego County.Urban growth is currently developing regions to the east of Tijuana Municipality and south of Rosarito Beach, where developers are building many new residential communities while in San Diego it is observed to the northeast along the Interstate 15 corridor to Temecula and Murrieta.Greater Ensenada is more frequently than not considered part of the region given its proximity and inter-connectivity with the metropolitan area.