Diamond Bar is located in the state of California and a city in the eastern part of Los Angeles County, and it was named after the branding iron “diamond over a bar” that was registered in 1918 by Frederick E. Lewis, who was the ranch owner. The city is the home to the Diamond Bar Country Estates, which is a guarded private community, along with the Los Angeles County golf course. It sits along the Pomona and Orange junction freeways and is primarily residential with several shopping centers that interspersed throughout the city. The city has many facilities that serve its residents, such as the Pomona Unified School District, as well as the International Polytechnic High School, and also has the first hydrogen fueling station that was built in Southern California.