Big Bear Lake is an incorporated city situated in San Bernardino County within the state of California, United States. It lies in the San Bernardino Mountains along the south shore of Big Bear Lake, surrounded entirely by the San Bernardino National Forest. The municipality occupies a total area of 6.5 square miles, with the majority being land and a small portion comprising water. It is positioned approximately 25 miles northeast of the city of San Bernardino and sits immediately west of the unincorporated town of Big Bear City.

The region was inhabited by the indigenous Serrano people for over two millennia before European exploration in 1845 by Benjamin Wilson, who named the area after the local grizzly bears. The population grew rapidly during the Southern California gold rush from 1861 to 1912. In 1921, Emile Jesserun built the Pan Hot Springs Hotel, establishing Big Bear as a premier mountain recreation area. The city was officially incorporated on November 28, 1980, following decades of development as a resort destination for Hollywood celebrities and vacationers.

The city is defined by its resort character and natural landmarks, including the Big Bear Solar Observatory on the north shore, which was completed in 1970. Winter sports facilities like Snow Summit, opened in 1952, anchor the area's recreational identity. The geography features an official elevation of 6,752 feet, making it the highest and coldest incorporated city in southern California. The surrounding forest areas require Adventure Passes for parking, while the city limits offer free parking, highlighting the distinction between municipal and national forest management.

Big Bear Lake attracts visitors through its year-round resort appeal, hosting traditions such as an annual Oktoberfest featuring the highest elevation beer garden in the United States. The area has a rich history in film production, serving as a location for numerous movies since the silent era and training camps for boxing champions like Mike Tyson. Summer activities focus on the lake, while winter draws skiers and snowboarders, supported by snow machines during low-snow years to maintain resort operations.

The population was 5,046 as of the 2020 census, though visitor numbers surge significantly during weekends due to its status as a popular destination. Access is primarily via highways 330, 38, and 18 from Southern California, with nearby airports at Ontario and Palm Springs. The climate features warm-summer Mediterranean conditions with significant winter snowfall averaging 58.6 inches per season, making it a distinct high-elevation environment compared to the lowlands of southern California.