Mountain Empire, San Diego

Rancho Jamul was a 8,926-acre (36.12 km2) Mexican land grant in present-day San Diego County, California given in 1829 by Mexican Governor José María de Echeandía to Pío Pico. In 1831 Governor Manuel Victoria reconfirmed the grant to Pío Pico. The grant extended from present day Jamul southeast to Dulzura. It is currently the 5,600-acre Rancho Jamul Ecological Reserve, operated by the California Department of Fish and Wildlife.

Hollenbeck Canyon Wildlife Area is located near Jamul and Dulzura in California. The former cattle ranch was designated a wildlife area in 2001, and forms a wildlife corridor between Otay Mountain Wilderness and Jamul Mountains under the protection of the California Department of Fish and Wildlife. The approximately 6,100-acre area is open to the public for activities including hunting, equestrian use, hiking, mountain-biking, and (hunting) dog training.

Cedar Canyon is a valley of the San Ysidro Mountains in San Diego County, California, extending from the northern slopes of Otay Mountain in the south to Otay Lakes Road in the north. Part of it is in the Otay Mountain Wilderness.

Lyons Peak is a prominent mountain in San Diego County, California. The top of the mountain is enclosed in an almost rectangular patch of the Cleveland National Forest. An old fire lookout tower is located at the peak. Lyons Peak is located on restricted land and trespassing is prohibited. The peak's toponym honors Nathaniel Lyon (1818–1861). As an army captain, he passed by the peak in 1851 while scouting a new route east to the desert.

The San Ysidro Mountains are a mountain range in southern San Diego County, California, and Baja California, Mexico. The mountains are a rugged coastal foothill range of the Peninsular Ranges system. Major peaks include the highest summit of the range, Otay Mountain, and the Cerro San Isidro which forms the southern extrusion of the range on the Mexican side of the border. The majority of the range is within the Otay Mountain Wilderness area, in the United States.

The Jamul Casino is a Native American gambling enterprise run by the Jamul Indian Village on their 6-acre reservation in Jamul, California. It was formerly the Hollywood Casino Jamul-San Diego. The president and general manager is Mary Cheeks.The casino has 1,700 slot machines and 40 table games. It is located 20 miles east of downtown San Diego.

The Jamul Indian Village of California is a federally recognized tribe of Kumeyaay Indians, who are sometimes known as Mission Indians.

Otay Mountain is a mountain in San Diego County, California. It is the highest summit of the San Ysidro Mountains. The mountain is located in the Otay Mountain Wilderness area. The Mexico-United States border runs along the south face of the mountain.

The Otay Mountain Wilderness is a U.S. Wilderness Area in San Diego County, California, 12 miles east of the community of Otay Mesa and just north of the Mexico-U.S. border. Some parts of the wilderness area rise quickly from sea level, reaching a peak of just over 3,500 feet (1,100 m) at the summit of Otay Mountain. Wilderness status was conferred on October 7, 1998, effectively preserving 18,500 acres under protection of the Wilderness Act, a component of the National Wilderness Preservation System. The legislation was signed by President Bill Clinton: 306  on December 11, 1999. The wilderness is managed by the Bureau of Land Management.

McGinty Mountain is a gabbroic mountain located in San Diego County, California near Jamul. Because of the gabbroic soil, the mountain supports numerous rare and endemic plant species, including half of California's population of the Dehesa nolina (Nolina interrata). The mountain belongs to an ecological preserve collectively managed by The Nature Conservancy, the California Department of Fish and Wildlife, and the San Diego National Wildlife Refuge. The mountain is accessible through a 4.7 mi (7.6 km) long out-and-back hiking trail.

The Jamul Mountains are a mountain range of the Peninsular Ranges System. They are located in southernmost San Diego County, Southern California. The Mexico–United States border is nearby to the south. There is a trail starting at Upper Otay Lake that leads over the western part of the range.

Jamul (; Kumeyaay: Ha-mul, meaning "sweet water") is a census-designated place (CDP) in San Diego County, California, United States. Jamul had a population of 6,163 at the 2010 census. Jamul suffered from the Valley Fire, one of the 2020 California wildfires.