Santa Clarita is the fourth largest city in Los Angeles County, California, United States and the twenty-sixth largest city in the State of California. The California Department of Finance estimated the city population as of January 1, 2009 at 177,150. Including unincorporated areas of the Santa Clarita Valley, the population is estimated at over 275,000. It is located about 35 miles (56 km) northwest of downtown Los Angeles, and occupies most of the Santa Clarita Valley. It is a notable example of a U.S. edge city or boomburb. The FBI rates it as the sixth safest city in the United States with at least 100,000 inhabitants. (Nearby Simi Valley and Thousand Oaks, in Ventura County, traditionally alternate between the first and second spots on the list. ) Santa Clarita was ranked as number 18 of the top 100 places to live by Money magazine in 2006. Santa Clarita was incorporated in 1987 as the union of several previously existing communities, including Canyon Country, Newhall, Saugus, and Valencia, all of which are the land of the former Rancho San Francisco. Its principal boundaries are the Golden State (I-5) and Antelope Valley (SR-14) freeways; their merger in Newhall Pass at the city's southernmost point gives Santa Clarita its distinctive triangular appearance on the map. Santa Clarita's most notable attractions are the Six Flags Magic Mountain amusement park located just outside the city limits in unincorporated Los Angeles County, and the California Institute of the Arts (CalArts), located in Valencia.