The term built environment refers to the human-made surroundings that provide the setting for human activity, ranging in scale from buildings and parks or green space to neighborhoods and cities that can often include their supporting infrastructure, such as water supply, or energy networks. The built environment is a material, spatial and cultural product of human labor that combines physical elements and energy in forms for living, working and playing. It has been defined as “the human-made space in which people live, work, and recreate on a day-to-day basis”. The “built environment encompasses places and spaces created or modified by people including buildings, parks, and transportation systems”. In recent years, public health research has expanded the definition of "built environment" to include healthy food access, community gardens, “walkabilty", and “bikability”.
Los Angeles County, also known as L.A. County, officially the County of Los Angeles, is a county in the U.S. state of California. As of the 2010 census, the county has a population of 9,818,605, making it the most populous county in the United States. Los Angeles County alone is more populous than 42 individual U.S. states. The county seat is the city of Los Angeles, the largest city in California and the second-largest city in the United States (after New York City).
Los Angeles County also includes two offshore islands, San Clemente Island and Santa Catalina Island. The county is home to 88 incorporated cities and many unincorporated areas. At 4,083 square miles (10,570 km2), it is larger than the combined areas of the states of Rhode Island and Delaware.
The county is home to over a quarter of all California residents and is one of the most diverse counties in the country.