Ontario is a city in southwestern San Bernardino County, California, 35 miles (56 km) east of downtown Los Angeles. Located in the western part of the Inland Empire region, it lies just east of the Los Angeles county line and is part of the Greater Los Angeles Area. As of the 2010 Census, the city had a population of 163,924, up from 158,007 at the 2000 census, making it the county's fourth most populous city after San Bernardino, Fontana, and Rancho Cucamonga.
The climate of Ontario is semi-arid, with very hot summers and warm winters. Santa Ana Winds hit the area frequently in autumn and winter. Extremes range from 114 °F (46 °C) down to 25 °F (-4 °C). Ontario has a hot-summer.
Ontario has 25 public elementary schools, six public middle schools and five public high schools under the combined oversight of four school districts. There are also several private schools throughout the city as well as two private military schools. Ontario also has nine trade schools. The University of La Verne College of Law is located in downtown Ontario. National University, Argosy University, San Joaquin Valley College and Chapman University have a satellite campus near the Ontario Mills mall.
The Ontario International Airport provides domestic and limited international air travel. Because of the many manufacturing companies and warehouses in the city, the airport also serves as a major hub for freight. The city is also served by several major freeways. Interstate 10 and the Pomona Freeway (State Route 60) run east-west through the city. Interstate 10 is north of the Ontario airport while the Pomona freeway is south of the airport. Interstate 15 runs in the north-south directions at the eastern side of the city. State Route 83, also known as Euclid Avenue, also runs in the north-south direction at the western side of the city.
The city of Ontario has a number of hotels, night clubs and also offers numerous resturants offering a wide range of dining expereinces. The city also offers numerous parks and receational facilities.