San Ysidro Mountains

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.

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.

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.

The Mountain Empire is a rural area in southeastern San Diego County, California. The Mountain Empire subregion consists of the backcountry communities in southeastern San Diego County. The area is also sometimes considered part of the East County region of San Diego County.

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.

Gateway Energy Storage is a large-scale lithium-ion battery, operated by grid infrastructure developer LS Power. It has a storage capacity of 250 MWh, and it is located in Otay Mesa, California, on the outskirts of San Diego. It uses cells from LG Chem.The purpose of the battery is to provide power during times of peak demand after being charged with solar power during the day.

The Otay Mesa East Port of Entry is a planned border crossing between San Diego and Tijuana, approximately 2 miles east of the existing Otay Mesa Port of Entry. The crossing will connect the Otay Centenario borough of Tijuana with East Otay Mesa in unincorporated San Diego County, an as-yet undeveloped area slotted for future development including a business park. Although the crossing will allow cars and pedestrians, it is mainly designed for trucks and commercial vehicles. In July 2014, Mexican Undersecretary of Infrastructure of the Secretariat of Communications and Transportation Raúl Murrieta Cummings and the Secretary of the California Department of Transportation (Caltrans), Brian P. Kelly, signed a memorandum of understanding to build and put the new port of entry into operation. It was expected to be ready as early as 2017, and provide 27 northbound lanes from Tijuana to San Diego and 8 southbound lanes. The cost is estimated to be 2 billion Mexican pesos (about 99 million US dollars).Construction began at the initial ground breaking in August 2022, after long delays. Although earlier estimates suggested the project would be completed by late 2024, more recent estimates suggest construction may not be complete until 2026.

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.

The San Diego Correctional Facility, also known as the Otay Mesa Detention Facility, is a minimum / medium security federal prison for men, managed by Corrections Corporation of America under contract with the United States Marshals Service and U.S. Immigration and Customs Enforcement (ICE).The facility is situated in the San Ysidro Mountains foothills of Otay Mesa overlooking the U.S.-Mexico border. The Otay Mesa site is shared with four other properties related to law enforcement: Richard J. Donovan Correctional Facility, operated by the California Department of Corrections and Rehabilitation. George Bailey County Detention facility, operated by the County of San Diego East Mesa Reentry Facility, operated by the City of San Diego Multi-jurisdictional law enforcement firearms training complex used by the FBI, the Customs Service, and local police forces.

The Otay River () is a river in southern San Diego County, California. The 25 mi (40 km) river begins at San Miguel Mountain, flows through the Upper and Lower Otay Reservoirs, and continues on between the southern part of the Chula Vista and the Otay Mesa West district of San Diego, to its river mouth on San Diego Bay.

Savage Dam is a dam across the Otay River in the San Ysidro Mountains of southwestern San Diego County, California. It is a concrete arch gravity structure 149 feet (45 m) high, and serves to store water from the San Diego Aqueduct's third pipeline for backup municipal uses in the San Diego metropolitan area. It is just over 6 miles (9.7 km) southeast of Chula Vista and 4 miles (6.4 km) north of the United States-Mexico border. The dam is named in honor of H. N. Savage, who directed its construction.The dam was originally completed in 1897 as an earthfill and steel structure called the Otay Dam by the Southern California Mountain Water Company to provide water storage. However, in 1916, heavy rains supposedly brought on by Charles Hatfield, a "rainmaker", hired by the city of San Diego to put an end to a drought, caused the dam to burst. The failure sent a wall of water 40 feet (12 m) high downstream, destroying buildings and bridges, and washing thousands of tons of sediment and wreckage into San Diego Bay. Eleven Japanese American farmers were killed. The dam was rebuilt as Savage Dam in 1918, and has functioned properly since.

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.