Montclair is a city in the Pomona Valley, in southwestern San Bernardino County, California, 35 miles (56 km) east of downtown Los Angeles.

The Serrano established their village along a creek named Arroyo de los Alisos, now named San Antonio Creek, which flowed along a route that is now Mills Avenue, the western border of the city.

In 1897, a "Township of Marquette" was founded within the borders of the modern city of Montclair.

A small settlement to the south of Monte Vista was established in 1907 and named "Narod".

Throughout the first half of the 20th century, the settlement was largely devoted to citrus orchards.

Due to conflict with the Post Office, which refused to open an office in Monte Vista due to a name conflict with a community in Northern California, the city was renamed Montclair on April 8, 1958.

Montclair is bordered by Pomona to the west, Claremont and Upland to the north, Ontario to the east, and Chino to the south.

Montclair, which is on the border with Los Angeles County, is in the Pomona Valley and part of the Inland Empire region.

The current mayor is Javier "John" Dutrey, and the other members of the city council are Mayor Pro-Tem Bill Ruh, Tenice Johnson, Corysa Martinez and Benjamin "Ben" Lopez.

[14] The Montclair Transcenter is a major commuter bus and rail hub, where many daily Metrolink, Foothill Transit, Omnitrans, and Silver Streak connections are available to downtown Los Angeles and points in between.